And lo On Sun, 28 Mar 2010 22:52:27 +0200, Darren New <dne### [at] sanrrcom>  
did spake thusly:

> Warp wrote:
>>   Maybe you could argue that science makes the *assumption* that  
>> measurements
>> correspond to reality, but as long as there's no evidence of the  
>> contrary,
>> there's no reason to think otherwise. Someone could argue this *is*  
>> faith.
>
> I think what makes it faith is the behavior in the face of  
> contradictions to what one has faith in.
>
> The behavior when showing a religious person things that tend to  
> contradict their faith is generally denial and looking for some way to  
> show you've misinterpreted their holy works or some such. The classic  
> example is if you show someone where the bible says God is evil, they  
> will tell you that you're misinterpreting the bible.
>
> If you tell a scientist that you have measurements that don't match  
> theory, the first assumption is that you measured incorrectly. The  
> second assumption is that the theory is wrong. I don't think there's  
> ever an assumption that reality is conspiring against you.

And the third option is that something unknown is influencing the results.  
If the theory matches the majority of results than the unknown influence  
becomes the most logical thing to check for.

Said influence may well turn out to be that reality is conspiring against  
you; although it's more likely to labeled "unknown" and only speculated  
about.

Now of course if reality is just conspiring against you such that only  
that one set of results should 'error' the only way to show it was if  
every result was different. If they're not it has no reason to be factored  
in.

The ball bounces, does it matter if it's red, blue or green? The Sun moves  
in the sky in a fixed pattern, does it matter if it's being pushed along  
by an invisible scarab? Science only gets involved if the answer is yes;  
faith gets involved even if the answer is no ;-)

-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com

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Darren New <dne### [at] sanrrcom> wrote:
> If you tell a scientist that you have measurements that don't match theory, 
> the first assumption is that you measured incorrectly. The second assumption 
> is that the theory is wrong.

  It's not that simple, actually. If you have 1000 different types of
measurements which confirm the theory and 1 measurement which contradicts
it, after corroborating that the measurement is valid the next step is not
to invalidate the theory. The next assumption is usually to see if there
are some *other* causes for the anomaly, and if nothing is found, whether
there are exceptional situations where the universe works differently from
the theory (in which case the theory might need fine-tuning).

  Two example cases are the so-called Pioneer anomaly and the flyby anomaly,
both of which seem to contradict general relativity (AFAIK it's not currently
known whether both are symptoms of the same effect or whether they are
unrelated).

  Just because these anomalies exist doesn't mean GR is bogus, even if
astrophysicists are scratching their heads with them.

-- 
                                                          - Warp

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On 03/28/10 12:06, Orchid XP v8 wrote:
>> 1) That reality works substantially in accordance with measurements.
> 
> If you mean "the universe is deterministic", well if that isn't the
> case, it is impossible to know anything, and we can stop now. There, we
> just explored every possible consequence of that hypothesis. Now if we
> assume that the universe *is* deterministic, we have quite a lot of
> consequences to explore - hence, science exists.

	Argument from extreme. The universe could be *mostly* deterministic,
but not entirely.


-- 
Why do toasters always have a setting that burns the toast to a horrible
crisp, which no decent human being would eat?

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On 03/28/10 13:52, Darren New wrote:
>>   Maybe you could argue that science makes the *assumption* that
>> measurements
>> correspond to reality, but as long as there's no evidence of the
>> contrary,
>> there's no reason to think otherwise. Someone could argue this *is*
>> faith.
> 
> I think what makes it faith is the behavior in the face of
> contradictions to what one has faith in.
> 
> The behavior when showing a religious person things that tend to
> contradict their faith is generally denial and looking for some way to
> show you've misinterpreted their holy works or some such. The classic
> example is if you show someone where the bible says God is evil, they
> will tell you that you're misinterpreting the bible.
> 
> If you tell a scientist that you have measurements that don't match
> theory, the first assumption is that you measured incorrectly. The
> second assumption is that the theory is wrong. I don't think there's
> ever an assumption that reality is conspiring against you.

	Well sure - but that's because they take it on faith that reality
doesn't conspire against you in that manner (as you pointed out originally).

-- 
Why do toasters always have a setting that burns the toast to a horrible
crisp, which no decent human being would eat?

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On 03/28/10 10:58, Darren New wrote:
> Darren New wrote:
>> I contend that there are at least two things most scientists take on
>> faith, without supporting evidence:
> 
> Oh, one more:
> 
> 3) Reality is consistent.
> 3A) The physical laws don't change. To the extent they change,
>     there is a physical law telling you how the laws change.
> 3B) The physical laws are consistent. (E.g., There *is* an
>     as-yet-undiscovered scientific theory unifying QM and GR.)
	
	That *is* a big assumption.	


-- 
Why do toasters always have a setting that burns the toast to a horrible
crisp, which no decent human being would eat?

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Neeum Zawan wrote:
> Why do toasters always have a setting that burns the toast to a horrible
> crisp, which no decent human being would eat?

That's a good question.  The sort of thing that occurs to me all the time, 
really.

I found out in Dallas that my security badge was apparently authorized to 
unlock the building but not authorized to turn off the burglar alarm. Why 
would you even *make* a system where it was possible to configure it that way?

-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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Warp wrote:
>   Just because these anomalies exist doesn't mean GR is bogus, even if
> astrophysicists are scratching their heads with them.

I would classify them under "measured wrong". I.e., there's something 
unaccounted for in the measurement.  I guess you could classify evil spirits 
as "unaccounted for". :-)

-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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On 28-3-2010 21:06, Orchid XP v8 wrote:

> If you mean "the universe is deterministic", well if that isn't the 
> case, it is impossible to know anything, and we can stop now.

Depending a bit on what you mean by deterministic, but in my definition 
the universe isn't. That is what Einstein-Podolski-Rosen was about.

> Science is, by definition, only concerned with that which is provable. 
> This isn't necessarily what is true, just what you can prove.

Which doesn't stop scientists from being mostly concerned about their 
own position and securing the next grant (even if they need to stab a 
colleague in the back).

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And lo On Mon, 29 Mar 2010 17:52:17 +0200, Darren New <dne### [at] sanrrcom>  
did spake thusly:

> Neeum Zawan wrote:
>> Why do toasters always have a setting that burns the toast to a horrible
>> crisp, which no decent human being would eat?
>
> That's a good question.  The sort of thing that occurs to me all the  
> time, really.

Try toasting a frozen slice of bread on the 'normal' setting.

> I found out in Dallas that my security badge was apparently authorized  
> to unlock the building but not authorized to turn off the burglar alarm.  
> Why would you even *make* a system where it was possible to configure it  
> that way?

Depends on the setup. Off the top of my head imagine a situation with a  
night-guard on reception. The building is locked, but the alarms aren't  
on. Now if the building can't be locked without the alarms being activated  
that's a pointless function of the card.

-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com

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Phil Cook v2 wrote:
> Depends on the setup. Off the top of my head imagine a situation with a 
> night-guard on reception. The building is locked, but the alarms aren't 
> on. Now if the building can't be locked without the alarms being 
> activated that's a pointless function of the card.

Yes, but that's not the problem. Indeed, that's how it works now.

The problem is that the card unlocks the door but does *not* turn off the 
alarm. The right answer, in other words, is to disallow the card from 
unlocking the door if the alarm is already set. Because as it stands now, 
going into the building sets off the alarm, with no way to turn that off.

-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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On 29-3-2010 18:17, Darren New wrote:
> Phil Cook v2 wrote:
>> Depends on the setup. Off the top of my head imagine a situation with 
>> a night-guard on reception. The building is locked, but the alarms 
>> aren't on. Now if the building can't be locked without the alarms 
>> being activated that's a pointless function of the card.
> 
> Yes, but that's not the problem. Indeed, that's how it works now.
> 
> The problem is that the card unlocks the door but does *not* turn off 
> the alarm. The right answer, in other words, is to disallow the card 
> from unlocking the door if the alarm is already set. Because as it 
> stands now, going into the building sets off the alarm, with no way to 
> turn that off.

just do that a couple of times then they have to fix it.

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Darren New <dne### [at] sanrrcom> wrote:
> Warp wrote:
> >   Just because these anomalies exist doesn't mean GR is bogus, even if
> > astrophysicists are scratching their heads with them.

> I would classify them under "measured wrong". I.e., there's something 
> unaccounted for in the measurement.  I guess you could classify evil spirits 
> as "unaccounted for". :-)

  It's just odd that it affects only flybys but not eg. satellites in orbit
or the Moon. Those work exactly like predicted by GR. (For example the
distance between the Earth and the Moon has been measured for 40 years
with an accuracy of about 1 cm, and this distance has changed exactly as
predicted by GR. There are tons and tons of other such measurements as well.
The flyby anomaly is an oddity with no currently known explanation.)

-- 
                                                          - Warp

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Warp wrote:
> The flyby anomaly is an oddity with no currently known explanation.)

Yeah. I've heard several proposed theories, and I thought I remembered them 
having figured out what was going on. But of course people say this, then 
retract it, and say something else, so it's hard to keep up.

Me, I think GR is subtly wrong/incomplete. It'll be interesting to see *how* 
wrong it is when people finally figure out how to unify it. I think even a 
tiny bit of error over universe-sized differences could make for fairly 
noticeable differences.

They also keep finding stuff happening like finding that over intergalactic 
distances, different wavelengths of light move at different speeds, which 
I'm pretty sure completely screws up the fundamentals of QM as well. (They 
postulate it has to do with the wavelength of the light vs the size of 
quantum foam or some such incomprehensible babble.)

In any case, it's all fun to watch the cutting edge.

-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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Darren New wrote:
> Argumentative religious people often seem to comment that science 
> requires faith. Argumentative non-religious people say that's nonsense, 
> since there is evidence.  I contend that there are at least two things 
> most scientists take on faith, without supporting evidence:
> 
> 1) That reality works substantially in accordance with measurements.

> 2) Humans aren't special.

3) That the world of our experience is the only one.

4) That the world of our experience has always operated precisely as we 
observe it to operate today.

Many things claimed by the non-religious worldview (such as the age of 
the earth) demand that things like the speed of light and the decay rate 
of radioactive isotopes have always had the values we measure them to 
have today.  They also demand that no major changes have been forced 
upon the world of our experience by some agency, existing outside of 
that world, at times where we have been unable to make observations.

These are no small assumptions.  We measure carbon-14 as having a 
half-life of ~5000 years, but our claim that it had the same half-life 
in King Tut's day is not based on observation, but on the assumption 
that some things about nature never change.  How do we *know* it does 
not change?  Not in the same way that we know many other things about 
nature (through observation).

In a like manner, how do we *know* that our world has operated without 
any interference from any other?  To be honest, we don't.  To know for 
sure, one way or the other, requires use to have observed nature for its 
entire duration.  Sure, we observe no such interruptions now, but that 
in no way proves that none have happened in the part nor will happen in 
the future.  Perhaps some mad scientist in the next parallel over is 
about to have an experiment go awry (or has such an experiment go awry 
at some point in the past), and its effect spill over to where we can 
see them.

Compounding the issue with #4 is the scientific concern with 
repeatability.  We don't control what happens in the next plane over, 
and therefore cannot rein them into a systematic investigation, not even 
to verify any reported observations.  Science regards the non-repeatable 
as unreliable and ultimately negligible.

This really goes with the territory.  Principle #1 above is absolutely 
vital to science; if we cannot assume that our sense reliably report to 
us the state of the world, then we cannot do science at all.  In a like 
manner, if we cannot assume certain things about the operation of nature 
to be constant (assumptions 3 and 4), then investigations into the 
origin of life, and the state of the universe at much earlier periods, 
are like a blind man trying to find his way across a strange city, 
unassisted.

It is not easy to admit that we, in conducting science, have made 
assumptions that we have no hope of proving; but this by no means 
justifies the habit of denying that the wrongness of these assumptions 
remains a possibility.  Even though admitting these assumptions will 
appear to us to hand a victory to science's enemies, we cannot do 
science if we deny unpleasant truths.

Regards,
John

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On 29-3-2010 20:08, John VanSickle wrote:
> Darren New wrote:
>> Argumentative religious people often seem to comment that science 
>> requires faith. Argumentative non-religious people say that's 
>> nonsense, since there is evidence.  I contend that there are at least 
>> two things most scientists take on faith, without supporting evidence:
>>
>> 1) That reality works substantially in accordance with measurements.
> 
>> 2) Humans aren't special.
> 
> 3) That the world of our experience is the only one.
> 
> 4) That the world of our experience has always operated precisely as we 
> observe it to operate today.

These two are not basic assumptions. They follow from application of 
Occam's razor. But perhaps we can promote the belief in the razor to a 
form faith.

> 
> Many things claimed by the non-religious worldview (such as the age of 
> the earth) demand that things like the speed of light and the decay rate 
> of radioactive isotopes have always had the values we measure them to 
> have today.  They also demand that no major changes have been forced 
> upon the world of our experience by some agency, existing outside of 
> that world, at times where we have been unable to make observations.
> 
> These are no small assumptions.  We measure carbon-14 as having a 
> half-life of ~5000 years, but our claim that it had the same half-life 
> in King Tut's day is not based on observation, but on the assumption 
> that some things about nature never change.  How do we *know* it does 
> not change?  Not in the same way that we know many other things about 
> nature (through observation).

What people do is precisely measure decay rates now and compare it with 
20 years ago. This will give an upper boundary on change. Also these 
figures are compared with independent measurements like tree rings and 
yearly ice deposits. I though that there is no indication that things 
have changed over time yet.
NB we are still puzzled by the fine structure constant. If we don't know 
why it has that value, it might not be a constant.

I do understand what you mean, but for me the assumption that the laws 
of physics were the same 10k or 100M years ago is a much smaller step 
than assuming that someone or something that has no physical presence 
anymore did at some point in time something that was contrary to every 
physical law that now seems to be operating.

> In a like manner, how do we *know* that our world has operated without 
> any interference from any other?  To be honest, we don't.  To know for 
> sure, one way or the other, requires use to have observed nature for its 
> entire duration.  Sure, we observe no such interruptions now, but that 
> in no way proves that none have happened in the part nor will happen in 
> the future.  Perhaps some mad scientist in the next parallel over is 
> about to have an experiment go awry (or has such an experiment go awry 
> at some point in the past), and its effect spill over to where we can 
> see them.
> 
> Compounding the issue with #4 is the scientific concern with 
> repeatability.  We don't control what happens in the next plane over, 
> and therefore cannot rein them into a systematic investigation, not even 
> to verify any reported observations.  Science regards the non-repeatable 
> as unreliable and ultimately negligible.
> 
> This really goes with the territory.  Principle #1 above is absolutely 
> vital to science; if we cannot assume that our sense reliably report to 
> us the state of the world, then we cannot do science at all.  In a like 
> manner, if we cannot assume certain things about the operation of nature 
> to be constant (assumptions 3 and 4), then investigations into the 
> origin of life, and the state of the universe at much earlier periods, 
> are like a blind man trying to find his way across a strange city, 
> unassisted.
> 
> It is not easy to admit that we, in conducting science, have made 
> assumptions that we have no hope of proving; but this by no means 
> justifies the habit of denying that the wrongness of these assumptions 
> remains a possibility.  Even though admitting these assumptions will 
> appear to us to hand a victory to science's enemies, we cannot do 
> science if we deny unpleasant truths.

AFAIC we always have in the back of our minds that we may be wrong. In 
physics the basic assumption is that we are. And I don't think you can 
find a physicist that really thinks that QM or GR is the final word.
Sometimes ( = too often) however, people have other motives apart from 
wanting to know how it all works. Many scientists will loose large sums 
of (grant) money if they are proven to be wrong. In general they will be 
the older people. Big changes in perception therefore often take a 
generation, because the people new in the field have not yet invested a 
lot in the old view.

That is why I am not happy with the current trend of increasing 
dependency on grant money for all scientists working at the 
universities. This money is often awarded (divided) by (among) the 
current top in the field. That is a recipe for stagnation.
It is also why I am in favor of limited lifespans (but we already 
covered that a few months ago).

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On 28-3-2010 19:50, Darren New wrote:
> Argumentative religious people often seem to comment that science 
> requires faith. Argumentative non-religious people say that's nonsense, 
> since there is evidence.  I contend that there are at least two things 
> most scientists take on faith, without supporting evidence:
> 
> 2) Humans aren't special.

I think there is evidence for that. Almost nothing in modern medicine or 
biology makes sense if we were special.

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On 03/29/10 08:52, Darren New wrote:
> Neeum Zawan wrote:
>> Why do toasters always have a setting that burns the toast to a horrible
>> crisp, which no decent human being would eat?
> 
> That's a good question.  The sort of thing that occurs to me all the
> time, really.

	Probably because they're used to toast things other than toast.

-- 
Why do toasters always have a setting that burns the toast to a horrible
crisp, which no decent human being would eat?

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John VanSickle wrote:
> 3) That the world of our experience is the only one.

Well, if there's more than one, and we can't experience it, I'd say it 
doesn't particularly matter. What most people mean by that, tho, is that we 
*rarely* experience it.

If there's really another world in which God lives, is it actually a 
different world if God actively intervenes in ours?

> 4) That the world of our experience has always operated precisely as we 
> observe it to operate today.

I don't think science assumes that at all.

> Many things claimed by the non-religious worldview (such as the age of 
> the earth) demand that things like the speed of light and the decay rate 
> of radioactive isotopes have always had the values we measure them to 
> have today.  

No they don't. They're measured in different ways and they agree.

> They also demand that no major changes have been forced 
> upon the world of our experience by some agency, existing outside of 
> that world, at times where we have been unable to make observations.

True. I think there's a general assumption that there isn't a conspiracy to 
fool scientific measurements. (What amuses me is when the faithful will 
assert that it's their caring and loving god doing to lying.)

> These are no small assumptions.  We measure carbon-14 as having a 
> half-life of ~5000 years, but our claim that it had the same half-life 
> in King Tut's day is not based on observation, but on the assumption 
> that some things about nature never change.

This isn't true. You measure things like radioactive decay, and you compare 
it against rings in trees, and layers of arctic ice, and the numbers of 
generations of animal bones found in tar pits, and they all match up. This 
is one set of assumptions scientists don't really make without support. Of 
course, it helps that we actually have written records of when the mummies 
were mummified and such, as well as things like Oklo.

Certainly it's likely more common in astronomical fields, methinks, simply 
because the time frames and distances are far too large to be able to do 
more than estimate. All you can do is look at a large amount of pretty much 
static data and deduce things from that. For example, some of the hubble 
measurements are based on seeing stars in our galaxy behave a particular 
way, and stars in the neighboring galaxies behave a particular way, and 
assuming that stars too far away for paralax measurements behave the same 
way.  I'd put that under #2, myself.

> How do we *know* it does 
> not change?  Not in the same way that we know many other things about 
> nature (through observation).

By measuring things a bunch of different ways, then finding the consistencies.

> In a like manner, how do we *know* that our world has operated without 
> any interference from any other?  To be honest, we don't.

Tautologically. If they interfered, they're part of our world. :-)

> and its effect spill over to where we can see them.

I think that would make it open to scientific investigation. Certainly 
that's part of the whole "what caused the big bang" investigation.

> if we cannot assume certain things about the operation of nature 
> to be constant (assumptions 3 and 4), 

I don't think we assume those things. We check them.

> It is not easy to admit that we, in conducting science, have made 
> assumptions that we have no hope of proving;

I think we can certainly disprove that (for example) humans are at the 
middle of the universe or that evil spirits interfere in our measurements. 
(For example, all we need is Satan to appear and admit it.)

I'm thinking that most of the BS that religious people try to argue 
scientifically (like transitional fossils, or carbon dating, or etc) are 
easy to "prove" in a scientific way without assuming the universe has always 
operated under the same approximate set of laws.  But I do think there are a 
number of unprovable assumptions (like that that set of laws is in theory 
discoverable) that don't discredit science but rather power it.

-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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John VanSickle wrote:
> 3) That the world of our experience is the only one.

Actually, I think the whole "string theory" bits and "brane" bits are an 
investigation of exactly this. So I don't think this is a fundamental 
assumption.


-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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andrel wrote:
> On 28-3-2010 19:50, Darren New wrote:
>> Argumentative religious people often seem to comment that science 
>> requires faith. Argumentative non-religious people say that's 
>> nonsense, since there is evidence.  I contend that there are at least 
>> two things most scientists take on faith, without supporting evidence:
>>
>> 2) Humans aren't special.
> 
> I think there is evidence for that. Almost nothing in modern medicine or 
> biology makes sense if we were special.

How about the fact that the stars of the universe are all red-shifted the 
farther they get from *us*?  Or the fact that we seem to be the only 
creatures in the entire *universe* that broadcast radio signals?

(I don't necessarily mean "special" in terms of biology-on-earth, but 
special in a more universal sense.)

People don't say "the red shift shows everything is moving away from us" or 
"humans happen to live where time passes fastest in the universe." They say 
"the red shift shows everything is moving away from everything else."

(Actually, now that I think about it, "humans happen to live at the top of 
the universe where time passes fastest" completely explains *both* those 
bits of evidence. :-)

-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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Darren New wrote:
> I think we can certainly disprove that (for example) humans are at the
> middle of the universe or that evil spirits interfere in our
> measurements. (For example, all we need is Satan to appear and admit it.)

But, since any point of reference can only see outward, in the universe,
as far as light could travel since the beginning of the universe . . .
We are all at the center of it.



I really shouldn't try thinking like this, this late/early in the morning.

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On 30-3-2010 0:30, Darren New wrote:
> andrel wrote:
>> On 28-3-2010 19:50, Darren New wrote:
>>> Argumentative religious people often seem to comment that science 
>>> requires faith. Argumentative non-religious people say that's 
>>> nonsense, since there is evidence.  I contend that there are at least 
>>> two things most scientists take on faith, without supporting evidence:
>>>
>>> 2) Humans aren't special.
>>
>> I think there is evidence for that. Almost nothing in modern medicine 
>> or biology makes sense if we were special.
> 
> How about the fact that the stars of the universe are all red-shifted 
> the farther they get from *us*?  Or the fact that we seem to be the only 
> creatures in the entire *universe* that broadcast radio signals?

For the latter see the Drake equation.

> (I don't necessarily mean "special" in terms of biology-on-earth, but 
> special in a more universal sense.)
> 
> People don't say "the red shift shows everything is moving away from us" 
> or "humans happen to live where time passes fastest in the universe." 
> They say "the red shift shows everything is moving away from everything 
> else."

We say that because we believe in Lorentz invariance.

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> How about the fact that the stars of the universe are all red-shifted the 
> farther they get from *us*?

Once you have the information about the surrounding stars, isn't it quite 
trivial to show that from the point of view of *any* star, all other stars 
are red-shifted more the further away they are?

> Or the fact that we seem to be the only creatures in the entire *universe* 
> that broadcast radio signals?

Why the assumption that any intelligent lifeform would be broadcasting radio 
signals for any significant time in its existence?  To me that seems silly. 
Earth has been broadcasting radio for 100 years out of 4.5 billion, maybe we 
will continue to do so for another 10000 years until we find something 
better?  Those timescales are tiny compared to the variation in ages of 
other stars.

Also, really can you detect the radio signals from Earth more than a few 
light years away?  Isn't the signal going to be incredibly tiny and 
virtually impossible to detect?  And that's just a few light years, what 
about the other planets billions of light years away?

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Darren New wrote:
> John VanSickle wrote:

>> Many things claimed by the non-religious worldview (such as the age of 
>> the earth) demand that things like the speed of light and the decay 
>> rate of radioactive isotopes have always had the values we measure 
>> them to have today.  
> 
> No they don't. They're measured in different ways and they agree.

Although if the values for these constants are in fact the result of 
more fundamental properties of space and matter, then any shift in one 
could only happen with a corresponding shift in the others (for 
instance, the electric constant, the magnetic constant, and the speed of 
light, are all interrelated), and our benchmark is moving.

>> They also demand that no major changes have been forced upon the world 
>> of our experience by some agency, existing outside of that world, at 
>> times where we have been unable to make observations.
> 
> True. I think there's a general assumption that there isn't a conspiracy 
> to fool scientific measurements. (What amuses me is when the faithful 
> will assert that it's their caring and loving god doing to lying.)

It's a fair assumption to state that if miracles were happening in the 
world, science would be rather hobbled in its progress.  If a Supreme 
Being wanted science to progress at the fastest possible rate, He would 
refrain from causing miracles.

Which means that the lack of miracles proves nothing...

Regards,
John

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On 30-3-2010 13:46, scott wrote:
>> How about the fact that the stars of the universe are all red-shifted 
>> the farther they get from *us*?
> 
> Once you have the information about the surrounding stars, isn't it 
> quite trivial to show that from the point of view of *any* star, all 
> other stars are red-shifted more the further away they are?
> 
>> Or the fact that we seem to be the only creatures in the entire 
>> *universe* that broadcast radio signals?
> 
> Why the assumption that any intelligent lifeform would be broadcasting 
> radio signals for any significant time in its existence?  To me that 
> seems silly. Earth has been broadcasting radio for 100 years out of 4.5 
> billion, maybe we will continue to do so for another 10000 years until 
> we find something better? 

50 or 100 is a better estimate. We are already shutting down the 
Megawatt analog radio and TV transmission towers. Transmitters are 
continuously moving to less output and wider spectrum. Total power 
transmitted to outer space is decreasing and becoming less recognizable.

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Sabrina Kilian wrote:
> Darren New wrote:
>> I think we can certainly disprove that (for example) humans are at the
>> middle of the universe or that evil spirits interfere in our
>> measurements. (For example, all we need is Satan to appear and admit it.)
> 
> But, since any point of reference can only see outward, in the universe,
> as far as light could travel since the beginning of the universe . . .

That's already assuming that everywhere in the universe is homogenous. E.g., 
if we see a galaxy to the north that is halfway to the "edge" of the 
universe, you're assuming that if someone in that galaxy looked north, the 
"edge" of the universe would be the same distance away, rather than much 
closer.

I've seen discussions about the density of galaxies at distances, and how 
they don't match what you'd expect if the universe was expanding. But they 
do match what you'd expect if the universe was homogenous on a 4-sphere (or 
maybe a 5-sphere?) and time was simply running slower farther away because 
the normals weren't parallel. I.e., nothing's moving. It's just going slower 
from our point of view because it's closer to the horizon as seen by us. Of 
course, that's still homogenous, but does it really need to be?

-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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John VanSickle wrote:
> Darren New wrote:
>> John VanSickle wrote:
> 
>>> Many things claimed by the non-religious worldview (such as the age 
>>> of the earth) demand that things like the speed of light and the 
>>> decay rate of radioactive isotopes have always had the values we 
>>> measure them to have today.  
>>
>> No they don't. They're measured in different ways and they agree.
> 
> Although if the values for these constants are in fact the result of 
> more fundamental properties of space and matter, then any shift in one 
> could only happen with a corresponding shift in the others (for 
> instance, the electric constant, the magnetic constant, and the speed of 
> light, are all interrelated), and our benchmark is moving.

But that means it didn't change. If everything gets shorter, including your 
measuring sticks, then nothing changed. That's exactly how relativity works.

In any case, I'm talking about entirely independent measurements. The 
progress of the seasons is measured against the radioactivity of carbon-14 
which is measured against the tides caused by the moon which is measured 
against the rate of mutations in different species, etc etc etc.

It's how people know the moon has been slowing down and moving away, for 
example.

> It's a fair assumption to state that if miracles were happening in the 
> world, science would be rather hobbled in its progress.  If a Supreme 
> Being wanted science to progress at the fastest possible rate, He would 
> refrain from causing miracles.

Assuming the supreme being wanted scientific progress, which would seem to 
be in variance to numerous major religions. :-)

-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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andrel wrote:
>> How about the fact that the stars of the universe are all red-shifted 
>> the farther they get from *us*?  Or the fact that we seem to be the 
>> only creatures in the entire *universe* that broadcast radio signals?
> 
> For the latter see the Drake equation.

I'm familiar with it. What about it?

>> People don't say "the red shift shows everything is moving away from 
>> us" or "humans happen to live where time passes fastest in the 
>> universe." They say "the red shift shows everything is moving away 
>> from everything else."
> 
> We say that because we believe in Lorentz invariance.

Yep. That doesn't mean things are moving away from us. We can't measure 
whether they're moving away from us. All we can measure is the red shift. 
The assumption is that the red shift is caused by relative motion, and not 
the geometry of the universe.

-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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scott wrote:
>> How about the fact that the stars of the universe are all red-shifted 
>> the farther they get from *us*?
> 
> Once you have the information about the surrounding stars, isn't it 
> quite trivial to show that from the point of view of *any* star, all 
> other stars are red-shifted more the further away they are?

Only if you assume they're red-shifted *because* they're moving apart.

You're assuming that if you're in a distant galaxy and look back towards 
ours, ours too will be red-shifted, rather than blue-shifted. If, on the 
other hand, we were in the middle of the universe and time just happened to 
run fastest here, then we would be blue-shifted compared to other galaxies.

> Why the assumption that any intelligent lifeform would be broadcasting 
> radio signals for any significant time in its existence?  To me that 
> seems silly. Earth has been broadcasting radio for 100 years out of 4.5 
> billion, maybe we will continue to do so for another 10000 years until 
> we find something better?  Those timescales are tiny compared to the 
> variation in ages of other stars.

There's lots of discussion about what we should have found, including von 
Neumann probes and such. I think there are a lot of good arguments that (for 
example) given what we've accomplished in the last 100 years, someone who 
evolved intelligence only one billion years ago should already have 
colonized the galaxy.  The big numbers work both ways.

> Also, really can you detect the radio signals from Earth more than a few 
> light years away?  Isn't the signal going to be incredibly tiny and 
> virtually impossible to detect?  And that's just a few light years, what 
> about the other planets billions of light years away?

That's the argument, yes. It's certainly not conclusive. We can tell what 
planets have atmospheres and water from here, only 100 years after steam power.

-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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On 30-3-2010 18:11, Darren New wrote:
> andrel wrote:
>>> How about the fact that the stars of the universe are all red-shifted 
>>> the farther they get from *us*?  Or the fact that we seem to be the 
>>> only creatures in the entire *universe* that broadcast radio signals?
>>
>> For the latter see the Drake equation.
> 
> I'm familiar with it. What about it?

All we know that there are no radio signals broadcasted from a place 
exactly the right time ago to be just reaching us now, send towards us, 
and in a format that we recognize. Which is quite a long way away from a 
conclusion that no signals are send at all.

>>> People don't say "the red shift shows everything is moving away from 
>>> us" or "humans happen to live where time passes fastest in the 
>>> universe." They say "the red shift shows everything is moving away 
>>> from everything else."
>>
>> We say that because we believe in Lorentz invariance.
> 
> Yep. That doesn't mean things are moving away from us. We can't measure 
> whether they're moving away from us. All we can measure is the red 
> shift. The assumption is that the red shift is caused by relative 
> motion, and not the geometry of the universe.

I don't understand that last sentence, but that may be my physics 
background.

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andrel wrote:
> On 30-3-2010 18:11, Darren New wrote:
>> andrel wrote:
>>>> How about the fact that the stars of the universe are all 
>>>> red-shifted the farther they get from *us*?  Or the fact that we 
>>>> seem to be the only creatures in the entire *universe* that 
>>>> broadcast radio signals?
>>>
>>> For the latter see the Drake equation.
>>
>> I'm familiar with it. What about it?
> 
> All we know that there are no radio signals broadcasted from a place 
> exactly the right time ago to be just reaching us now, send towards us, 
> and in a format that we recognize. Which is quite a long way away from a 
> conclusion that no signals are send at all.

Yes. Hence the "seems to". Anyway, you understand my point even if you 
disagree. :-)

>> Yep. That doesn't mean things are moving away from us. We can't 
>> measure whether they're moving away from us. All we can measure is the 
>> red shift. The assumption is that the red shift is caused by relative 
>> motion, and not the geometry of the universe.
> 
> I don't understand that last sentence, but that may be my physics 
> background.


We assume that the distant galaxies are red-shifted *because* they are 
moving away from us. We don't assume that the Milky Way has the lowest speed 
of light in the universe, or that time runs slower the farther you get from 
humanity, or that the gravitational constant is slowly increasing the 
farther you get from humanity.  *If* you assume that all other places in the 
universe will see the same thing when they look around, *then* all the 
galaxies must be moving away from each other.  *If* you assume we're in a 
unique and privileged place in the universe, there are all kinds of things 
that could be causing it.


-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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On 30-3-2010 20:15, Darren New wrote:
> andrel wrote:
>> On 30-3-2010 18:11, Darren New wrote:
>>> andrel wrote:
>>>>> How about the fact that the stars of the universe are all 
>>>>> red-shifted the farther they get from *us*?  Or the fact that we 
>>>>> seem to be the only creatures in the entire *universe* that 
>>>>> broadcast radio signals?
>>>>
>>>> For the latter see the Drake equation.
>>>
>>> I'm familiar with it. What about it?
>>
>> All we know that there are no radio signals broadcasted from a place 
>> exactly the right time ago to be just reaching us now, send towards 
>> us, and in a format that we recognize. Which is quite a long way away 
>> from a conclusion that no signals are send at all.
> 
> Yes. Hence the "seems to". Anyway, you understand my point even if you 
> disagree. :-)

yes

>>> Yep. That doesn't mean things are moving away from us. We can't 
>>> measure whether they're moving away from us. All we can measure is 
>>> the red shift. The assumption is that the red shift is caused by 
>>> relative motion, and not the geometry of the universe.
>>
>> I don't understand that last sentence, but that may be my physics 
>> background.
> 
> 
> We assume that the distant galaxies are red-shifted *because* they are 
> moving away from us. We don't assume that the Milky Way has the lowest 
> speed of light in the universe, or that time runs slower the farther you 
> get from humanity, or that the gravitational constant is slowly 
> increasing the farther you get from humanity.  *If* you assume that all 
> other places in the universe will see the same thing when they look 
> around, *then* all the galaxies must be moving away from each other.  
> *If* you assume we're in a unique and privileged place in the universe, 
> there are all kinds of things that could be causing it.

hence my "We say that because we believe in Lorentz invariance" as a 
abbreviation of a couple of paragraphs like the one above ;)

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andrel wrote:
> hence my "We say that because we believe in Lorentz invariance" as a 
> abbreviation of a couple of paragraphs like the one above ;)

Lorentz invariance would explain it if time was running slower or the speed 
of light was different farther away as well.

-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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On 30-3-2010 20:29, Darren New wrote:
> andrel wrote:
>> hence my "We say that because we believe in Lorentz invariance" as a 
>> abbreviation of a couple of paragraphs like the one above ;)
> 
> Lorentz invariance would explain it if time was running slower or the 
> speed of light was different farther away as well.
> 

No, differential time- and lightspeeds are incompatible with lorentz 
invariance of physical laws, because they should be invariant under 
translation and uniform velocity changes.
In particular Maxwell's equations are lorentz invariant and they imply a 
*constant* velocity at which E and B fields propagate (generally known 
as c).

It might be possible to modify Maxwell's equations to allow timevarying 
lightspeed and find a new invariant that for times close to our own 
reduces to Lorentz invariance, but I have not heard of anybody doing 
that trick.

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On 3/28/2010 3:53 PM, Darren New wrote:
> Patrick Elliott wrote:
>> Still, its an interesting idea, and explains nicely why your desk will
>> never "jump" all into one corner of the room, for no reason.
>
> I think we already knew that. If you work out the probability that
> happens, it's exceedingly low.
>
Well, not really. The presumption is still that it *can* do so. However, 
if there is a limit on what things can do that, such that a desk doesn't 
simply have almost "no" chance of doing such a thing, but *absolutely no 
chance*, then you have a difference situation. That is the point. 
Standard QM insists its possible, just so insanely improbable that you 
will never see it happen. But, if QM gets even more greatly limited, or 
virtually switched off, for objects whose size and density exceeds some 
specific factor... That is a whole different ball game, since it means 
your QM is trapped, like air in a balloon, and no longer has the "range" 
needed to cause you desk to do such a thing.

-- 
void main () {
   If Schrödingers_cat is alive or version > 98 {
     if version = "Vista" {
       call slow_by_half();
       call DRM_everything();
     }
     call functional_code();
   }
   else
     call crash_windows();
}

<A HREF='http://www.daz3d.com/index.php?refid=16130551'>Get 3D Models, 
3D Content, and 3D Software at DAZ3D!</A>

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Patrick Elliott wrote:
> Well, not really. The presumption is still that it *can* do so. However, 
> if there is a limit on what things can do that, such that a desk doesn't 
> simply have almost "no" chance of doing such a thing, but *absolutely no 
> chance*, then you have a difference situation. That is the point. 

Well, sure, but I never heard of anyone postulating that.

> Standard QM insists its possible, just so insanely improbable that you 
> will never see it happen. But, if QM gets even more greatly limited, or 
> virtually switched off, for objects whose size and density exceeds some 
> specific factor... That is a whole different ball game, since it means 
> your QM is trapped, like air in a balloon, and no longer has the "range" 
> needed to cause you desk to do such a thing.

QM also has probabilities that cancel out, such that there's zero 
probability of something happening in a combination where either individual 
event could happen. E.g., electron 1 might go to location X[*]. Electron 2 
might go to location X. Electron 3 might go to location X. But there is zero 
probability that all three will go to location X. Also, the likelihood that 
a photon will go somewhere far away at anything other than very close to the 
speed of light is zero (and not just very low), because the probabilities 
actually cancel out. You don't need to postulate an upper size on QM 
locality to get impossible events. And when "improbable" is "1/10^500 that 
any particle in the universe will ever do that", then yeah, that's pretty 
much impossible too.



[*] "location" in spacetime, i.e., an "event".

-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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andrel wrote:
> No, differential time- and lightspeeds are incompatible with lorentz 
> invariance of physical laws, because they should be invariant under 
> translation and uniform velocity changes.

I see what you mean. Yes, I agree. My bad.

-- 
Darren New, San Diego CA, USA (PST)
   Yes, we're traveling together,
   but to different destinations.

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andrel wrote:
> On 30-3-2010 0:30, Darren New wrote:
>> How about the fact that the stars of the universe are all red-shifted
>> the farther they get from *us*?  Or the fact that we seem to be the only
>> creatures in the entire *universe* that broadcast radio signals?
> 
> For the latter see the Drake equation.

Or: http://xkcd.com/718/

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andrel wrote:
> On 30-3-2010 18:11, Darren New wrote:
>> andrel wrote:
>>>> How about the fact that the stars of the universe are all red-shifted
>>>> the farther they get from *us*?  Or the fact that we seem to be the
>>>> only creatures in the entire *universe* that broadcast radio signals?
>>>
>>> For the latter see the Drake equation.
>> 
>> I'm familiar with it. What about it?
> 
> All we know that there are no radio signals broadcasted from a place
> exactly the right time ago to be just reaching us now, send towards us,
> and in a format that we recognize. Which is quite a long way away from a
> conclusion that no signals are send at all.

I keep wondering... Is humanity *constantly* broadcasting radio signals in a 
simple format to nearby solar systems? What if aliens have a program exactly 
like SETI@Home, trying to find intelligence in noise from received radio 
signals, but neither party is sending anything?

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On 31-3-2010 4:40, Nicolas Alvarez wrote:
> andrel wrote:
>> On 30-3-2010 18:11, Darren New wrote:
>>> andrel wrote:
>>>>> How about the fact that the stars of the universe are all red-shifted
>>>>> the farther they get from *us*?  Or the fact that we seem to be the
>>>>> only creatures in the entire *universe* that broadcast radio signals?
>>>> For the latter see the Drake equation.
>>> I'm familiar with it. What about it?
>> All we know that there are no radio signals broadcasted from a place
>> exactly the right time ago to be just reaching us now, send towards us,
>> and in a format that we recognize. Which is quite a long way away from a
>> conclusion that no signals are send at all.
> 
> I keep wondering... Is humanity *constantly* broadcasting radio signals in a 
> simple format to nearby solar systems? What if aliens have a program exactly 
> like SETI@Home, trying to find intelligence in noise from received radio 
> signals, but neither party is sending anything?

The major things we have been sending is FM (and AM) modulated radio and 
TV. This is effectively a big signal in a very small bandwidth. If you 
make a spectrum it will turn up as an unexpected peak above the 
background. If you then become interested and look closer you will see 
that the spectral contend is not compatible with a line originating from 
an exited atom or molecule. So, if these aliens are at the right time 
and place and have a SETI project running they will detect us in a 
couple of centuries when the signal reaches them.
If they are listening but expect a different modulation scheme they 
might just skip the lucille ball show as a strange artifact.

ATM AFAIK nobody is sending a deliberately simple encoded message. I 
think the jury is not out on the question if that would be a good idea 
at all.

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> The major things we have been sending is FM (and AM) modulated radio and 
> TV. This is effectively a big signal in a very small bandwidth. If you 
> make a spectrum it will turn up as an unexpected peak above the 
> background. If you then become interested and look closer you will see 
> that the spectral contend is not compatible with a line originating from 
> an exited atom or molecule. So, if these aliens are at the right time and 
> place and have a SETI project running they will detect us in a couple of 
> centuries when the signal reaches them.

OOC how sensitive is the SETI equipment and project?  I mean how big must a 
signal be from 200 ly away that we are able to detect it with that system? 
Extrapolating from the Voyager power levels and distance, I make it that we 
need a 350 GW signal to be transmitted from 200 ly away.  Is that realistic 
to expect?

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And lo On Mon, 29 Mar 2010 18:17:10 +0200, Darren New <dne### [at] sanrrcom>  
did spake thusly:

> Phil Cook v2 wrote:
>> Depends on the setup. Off the top of my head imagine a situation with a  
>> night-guard on reception. The building is locked, but the alarms aren't  
>> on. Now if the building can't be locked without the alarms being  
>> activated that's a pointless function of the card.
>
> Yes, but that's not the problem. Indeed, that's how it works now.
>
> The problem is that the card unlocks the door but does *not* turn off  
> the alarm.

Yes I would consider that a flaw :-)




-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com

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On 1-4-2010 8:56, scott wrote:
>> The major things we have been sending is FM (and AM) modulated radio 
>> and TV. This is effectively a big signal in a very small bandwidth. If 
>> you make a spectrum it will turn up as an unexpected peak above the 
>> background. If you then become interested and look closer you will see 
>> that the spectral contend is not compatible with a line originating 
>> from an exited atom or molecule. So, if these aliens are at the right 
>> time and place and have a SETI project running they will detect us in 
>> a couple of centuries when the signal reaches them.
> 
> OOC how sensitive is the SETI equipment and project?  I mean how big 
> must a signal be from 200 ly away that we are able to detect it with 
> that system? 

I don't know.

> Extrapolating from the Voyager power levels and distance, I 
> make it that we need a 350 GW signal to be transmitted from 200 ly 
> away.  

The SETI equipment might even be somewhat more sensitive because they 
are using larger disks. Then again they don't know what exact frequency 
to tune into.

BTW I arrive at something more like 47 MW if the voyager is transmitting 
all its power, which is unlikely, so the number could even be much lower.


> Is that realistic to expect?

If you really want to broadcast a message anything is realistic.

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andrel wrote:
>> Is that realistic to expect?
> 
> If you really want to broadcast a message anything is realistic.

And what if they aim the message directly at us? I assume they can use less 
power if they are pointing exactly at the Earth.

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scott wrote:
> OOC how sensitive is the SETI equipment and project?  I mean how big must
> a signal be from 200 ly away that we are able to detect it with that
> system? Extrapolating from the Voyager power levels and distance, I make
> it that we
> need a 350 GW signal to be transmitted from 200 ly away.  Is that
> realistic to expect?

Eric Korpela, one of SETI@Home admins, replies:

> SETI@home has a sensitivity of about 1e-25 W/m^2, so if I'm doing my math
> right, a transmitter at 200 ly would need to be about 7e+12 W EIRP
> (effective isotropic radiated power). If the transmitter was attached to a
> telescope the size of AO, it would have a gain of about 2 million, so the
> actual transmitter would need to be about 3.5 MW total power.
>
> Of course for a directional transmitter ET would need to suspect we are
> here.

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And more info:

Eric Korpela wrote:
> Nicolas Alvarez wrote:
>> Eric Korpela wrote:
>>> SETI@home has a sensitivity of about 1e-25 W/m^2, so if I'm doing my
>>> math right, a transmitter at 200 ly would need to be about 7e+12 W EIRP
>>> (effective isotropic radiated power). If the transmitter was attached to
>>> a telescope the size of AO, it would have a gain of about 2 million, so
>>> the actual transmitter would need to be about 3.5 MW total power.
>>>
>>> Of course for a directional transmitter ET would need to suspect we are
>>> here.
>>
>> What if it's not directional but broadcast? How much power do the
>> 200ly-far aliens need to send a radio signal covering an entire
>> hemisphere*, so that a reasonable amount still reaches us (or rather
>> SETI's antenna)?
>
> That would be 7 TW. Which is the amount of power you can generate with a
> solar array 150 km x 150 km* in size (assuming 24% efficiency). That would
> be a bit more than our society could afford to spend on trying to
> broadcast our position.

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On 2-4-2010 0:21, Nicolas Alvarez wrote:
> andrel wrote:
>>> Is that realistic to expect?
>> If you really want to broadcast a message anything is realistic.
> 
> And what if they aim the message directly at us? I assume they can use less 
> power if they are pointing exactly at the Earth.
> 
Then they know we are here which implies that they noticed our radio or 
television broadcasts. So, the answer to your question will not be 
relevant within the next 3 centuries.

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>> Extrapolating from the Voyager power levels and distance, I make it that 
>> we need a 350 GW signal to be transmitted from 200 ly away.
>
> The SETI equipment might even be somewhat more sensitive because they are 
> using larger disks. Then again they don't know what exact frequency to 
> tune into.
>
> BTW I arrive at something more like 47 MW if the voyager is transmitting 
> all its power, which is unlikely, so the number could even be much lower.

I assumed that the power needed goes up with the square of distance, so used 
Google to calculate:

"(200 light years / 16.8e9 km)^2 * 23 W"

which actually gives 300 GW, but I think that's a big underestimate, as 
presumably Voyager is directing its 23 W directly at Earth, and not 
radiating out in a sphere.  If an alien world 200 ly away is radiating in 
all directions equally, it would need to be outputting much more than 300 GW 
in total.

Post a reply to this message

>>> What if it's not directional but broadcast? How much power do the
>>> 200ly-far aliens need to send a radio signal covering an entire
>>> hemisphere*, so that a reasonable amount still reaches us (or rather
>>> SETI's antenna)?
>>
>> That would be 7 TW. Which is the amount of power you can generate with a
>> solar array 150 km x 150 km* in size (assuming 24% efficiency). That 
>> would
>> be a bit more than our society could afford to spend on trying to
>> broadcast our position.

Good info, thanks!

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On 6-4-2010 9:03, scott wrote:
>>> Extrapolating from the Voyager power levels and distance, I make it 
>>> that we need a 350 GW signal to be transmitted from 200 ly away.
>>
>> The SETI equipment might even be somewhat more sensitive because they 
>> are using larger disks. Then again they don't know what exact 
>> frequency to tune into.
>>
>> BTW I arrive at something more like 47 MW if the voyager is 
>> transmitting all its power, which is unlikely, so the number could 
>> even be much lower.
> 
> I assumed that the power needed goes up with the square of distance, so 
> used Google to calculate:
> 
> "(200 light years / 16.8e9 km)^2 * 23 W"
> 
> which actually gives 300 GW, but I think that's a big underestimate, as 
> presumably Voyager is directing its 23 W directly at Earth, and not 
> radiating out in a sphere. 

You are absolutely correct of course, I seem to have forgotten the 
square. :(

> If an alien world 200 ly away is radiating 
> in all directions equally, it would need to be outputting much more than 
> 300 GW in total.

That too. Probably the most efficient way to do it is by modulating the 
output of a star. Either directly (controlled starquakes?) or by putting 
things in front of it (jupiter sized arrays of shutters?).
Only, SETI isn't looking for that.

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