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Einstein's General Theory of Relativity is nearly a hundred years old by
now, but I think it is only now, in the age of YouTube, that a
fundamental understanding starts seeping into common knowledge of what
the theory /really/ means.
For instance, according to the General Theory of Relativity,
gravitational pull is caused by the curvature of spacetime. That's what
it says, isn't it? Right?
Err... nope.
What the General Theory of Relativity /really/ says is that there is /no
such thing/ as gravitational pull. To the contrary: What really makes
you stick to the ground is not a force pushing /you/ /down/, but a force
pushing /the ground/ /up/. More specifically, the electromagnetic forces
between the atoms of the earth push it apart with such a force that the
ground races upward at an acceleration of 9.81 m/s^2 - and all the while
the fabric of space near and at earth just contracts at an equivalent
rate, shriveling like the surface of a punctured balloon, so that the
effective distance between the atoms never gets any bigger despite their
accelerated motion through space.
I had been pondering this for a few days now, when I stumbled across
this video which I think gets the idea across quite well:
https://youtu.be/NblR01hHK6U
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On 10/18/2015 3:44 AM, clipka wrote:
> Einstein's General Theory of Relativity is nearly a hundred years old by
> now, but I think it is only now, in the age of YouTube, that a
> fundamental understanding starts seeping into common knowledge of what
> the theory /really/ means.
>
> For instance, according to the General Theory of Relativity,
> gravitational pull is caused by the curvature of spacetime. That's what
> it says, isn't it? Right?
>
> Err... nope.
>
> What the General Theory of Relativity /really/ says is that there is /no
> such thing/ as gravitational pull. To the contrary: What really makes
> you stick to the ground is not a force pushing /you/ /down/, but a force
> pushing /the ground/ /up/. More specifically, the electromagnetic forces
> between the atoms of the earth push it apart with such a force that the
> ground races upward at an acceleration of 9.81 m/s^2 - and all the while
> the fabric of space near and at earth just contracts at an equivalent
> rate, shriveling like the surface of a punctured balloon, so that the
> effective distance between the atoms never gets any bigger despite their
> accelerated motion through space.
>
> I had been pondering this for a few days now, when I stumbled across
> this video which I think gets the idea across quite well:
>
> https://youtu.be/NblR01hHK6U
>
So we should think that instead of the Earth attracting the apple with a
force of, say, 1.0 N. The apple attracts the Earth with a force of
5.86E+25 N. Makes sense.
You know, I find it hard to give any credence to someone who talks so
fast. A sure sign that they are trying to put one over on you. IMO
Mass of an "average" apple = 0.102 Kg
http://hypertextbook.com/facts/2004/WaiWingLeung.shtml
Mass of the Earth = 5.97E+24 Kg
(Google)
--
Regards
Stephen
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On 10/18/2015 7:03 AM, Stephen wrote:
> The apple attracts the Earth with a force of 5.86E+25 N. Makes sense.
Woops! I forgot to mention inertia. :-(
--
Regards
Stephen
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Am 18.10.2015 um 08:03 schrieb Stephen:
> On 10/18/2015 3:44 AM, clipka wrote:
>> Einstein's General Theory of Relativity is nearly a hundred years old by
>> now, but I think it is only now, in the age of YouTube, that a
>> fundamental understanding starts seeping into common knowledge of what
>> the theory /really/ means.
>>
>> For instance, according to the General Theory of Relativity,
>> gravitational pull is caused by the curvature of spacetime. That's what
>> it says, isn't it? Right?
>>
>> Err... nope.
>>
>> What the General Theory of Relativity /really/ says is that there is /no
>> such thing/ as gravitational pull. To the contrary: What really makes
>> you stick to the ground is not a force pushing /you/ /down/, but a force
>> pushing /the ground/ /up/. More specifically, the electromagnetic forces
>> between the atoms of the earth push it apart with such a force that the
>> ground races upward at an acceleration of 9.81 m/s^2 - and all the while
>> the fabric of space near and at earth just contracts at an equivalent
>> rate, shriveling like the surface of a punctured balloon, so that the
>> effective distance between the atoms never gets any bigger despite their
>> accelerated motion through space.
>>
>> I had been pondering this for a few days now, when I stumbled across
>> this video which I think gets the idea across quite well:
>>
>> https://youtu.be/NblR01hHK6U
>>
>
>
> So we should think that instead of the Earth attracting the apple with a
> force of, say, 1.0 N. The apple attracts the Earth with a force of
> 5.86E+25 N. Makes sense.
No, no - not at all.
What happens is that Earth, by virtue of having mass, gobbles up space
inside and around it. Always. Constantly. Whether there are any apples
out there or not. (So does the apple, but that's negligible compared to
Earth's dietary budget.) There's no acceleration or even movement
involved there /per se/ - in the vicinity of matter, distances just
shrink over time. Fast.
If it was only for this mechanism, earth would shrivel to nothingness in
a matter of... minutes? hours? Dunno, but certainly in less than a day.
Space between the elementary particles would just shrink to zero.
Fortunately, electromagnetic force comes to our rescue: The electron
clouds of any two atoms in the universe repel each other. Partially this
is compensated by the fact that the electron clouds of any atom in the
universe also attracts the nucleus of any other atom, but on average the
net EM force is repelling. And there are a lot of atoms in the Earth. So
the atoms making up earth constantly accelerate away from each other.
Earth is exploding.
Now while this seems even more bad news, it is important to note that
the repelling EM force heavily depends on the distance between the
atoms, much more so than the space-gobbling mechanism does. So while
space is busy shriveling away and Earth is busy exploding within this
space, these two mechanisms have long reached an equilibrium: The
distance between Earth's center and its surface is constant (save for
some other minor effects, such as Earth accreting more solid material
and evaporating light gases such as Helium).
But even though Earth's radius is constant, Earth's surface still /does/
accelerate upward. Not because it is attracted by apples out there, mind
you - to the contrary: Earth and the dropping apple /repel/ each other.
A tiny bit. But much more so, Earth is repelling itself, and hurtles
onward towards the unsuspecting dropping apple - until the two come so
close that EM forces between Earth and the apple suddenly skyrocket, and
(after a bit of bouncing around) come into equlibrium with the collapse
of space. The apple now races outwards along with Earth's surface.
Whoosh.
We're riding an explosion that is the only thing standing between us and
the formation of a black hole.
Also, think of this: If you throw an apple, it moves through space in a
/straight/ line - any apparent curvature of its trajectory is due to
Earth's surface constantly accelerating upwards. Not towards the apple
but away from Earth's center. In a lump of space that's busy shrinking.
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The application of Ockams's razor tells me that this is not correct.
I shall be more inclined to consider the day Roger Penrose confirms ;-)
--
Thomas
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I like that idea, as batshit crazy as it sounds. Riding an explosion away from
a black hole is poetic imagery at its finest.
But wait. Isn't the fabric of spacetime itself expanding and accelerating?
Perhaps our little muddy black hole chomps so much of ut away that it remains
constant in the vicinity...
oh well, I always hoped dinos back then would be today as small as a chicken,
aside from their by now equally expanded skeletons...
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>> Makes sense.
>
> No, no - not at all.
>
Sorry, I was in a rush and forgot the "Like Hell it does" icon.
> What happens is that Earth, by virtue of having mass, gobbles up space
> inside and around it. Always. Constantly. Whether there are any apples
> out there or not. (So does the apple, but that's negligible compared to
> Earth's dietary budget.) There's no acceleration or even movement
> involved there /per se/ - in the vicinity of matter, distances just
> shrink over time. Fast.
>
> If it was only for this mechanism, earth would shrivel to nothingness in
> a matter of... minutes? hours? Dunno, but certainly in less than a day.
> Space between the elementary particles would just shrink to zero.
>
> Fortunately, electromagnetic force comes to our rescue: The electron
> clouds of any two atoms in the universe repel each other. Partially this
> is compensated by the fact that the electron clouds of any atom in the
> universe also attracts the nucleus of any other atom, but on average the
> net EM force is repelling. And there are a lot of atoms in the Earth. So
> the atoms making up earth constantly accelerate away from each other.
> Earth is exploding.
>
To my untutored eyes* that sounds* like stability.
Getting my metaphors a bit mixed. I know.
> Whoosh.
>
> We're riding an explosion that is the only thing standing between us and
> the formation of a black hole.
>
An explosion with an average velocity of 0 m/s?
Scary.
>
> Also, think of this: If you throw an apple, it moves through space in a
> /straight/ line - any apparent curvature of its trajectory is due to
> Earth's surface constantly accelerating upwards. Not towards the apple
> but away from Earth's center. In a lump of space that's busy shrinking.
>
If you say so. But consider using another inertial frame of reference.
One that contains both the Earth and the apple. Which object, the Earth
or the apple, travels a greater distance in the same time frame?
I hazard a guess that it will be the apple that has the greater velocity
and thus acceleration.
Sorry, I wuz an enjuneer.
--
If you eat chocolate that you did not want to eat. Then it does not
count as chocolate.
Sir Terry P.
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> What happens is that Earth, by virtue of having mass, gobbles up space
> inside and around it. Always. Constantly. Whether there are any apples
> out there or not. (So does the apple, but that's negligible compared to
> Earth's dietary budget.) There's no acceleration or even movement
> involved there /per se/ - in the vicinity of matter, distances just
> shrink over time. Fast.
>
> If it was only for this mechanism, earth would shrivel to nothingness in
> a matter of... minutes? hours? Dunno, but certainly in less than a day.
> Space between the elementary particles would just shrink to zero.
>
> Fortunately, electromagnetic force comes to our rescue: The electron
> clouds of any two atoms in the universe repel each other. Partially this
> is compensated by the fact that the electron clouds of any atom in the
> universe also attracts the nucleus of any other atom, but on average the
> net EM force is repelling. And there are a lot of atoms in the Earth. So
> the atoms making up earth constantly accelerate away from each other.
> Earth is exploding.
If gravity (or rather, mass) causes space to contract and get gobbled
up, this must mean then that EM forces (and other equations?) must
somehow be able to measure distances "outside" of this distorted and
gobbled up space? There must be an external "real" space that is somehow
related to the distored spacetime by the distribution of mass around.
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Am 18.10.2015 um 16:29 schrieb Stephen:
>> Also, think of this: If you throw an apple, it moves through space in a
>> /straight/ line - any apparent curvature of its trajectory is due to
>> Earth's surface constantly accelerating upwards. Not towards the apple
>> but away from Earth's center. In a lump of space that's busy shrinking.
>>
>
> If you say so. But consider using another inertial frame of reference.
> One that contains both the Earth and the apple. Which object, the Earth
> or the apple, travels a greater distance in the same time frame?
> I hazard a guess that it will be the apple that has the greater velocity
> and thus acceleration.
Whatever frame of reference you choose - if it is truly inertial, you'll
always find the apple (while airborne) moving at constant velocity (or
remaining at rest, which is a special case thereof), and Earth's surface
accelerating radially from its center at 9.81 m/s^2. (As long as you
ignore aerodynamic drag and remain sufficiently close to Earth's surface
and the apple, that is.)
(Hint: What makes a frame of reference inertial? The fact that it
doesn't accelerate. How can you test it? By releasing some item with an
initial velocity of v=0 relative to the frame of reference, and
verifying that the item remains stationary. If you like, do the
experiment inside an elevator cabin with no windows.)
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Am 19.10.2015 um 09:18 schrieb scott:
> If gravity (or rather, mass) causes space to contract and get gobbled
> up, this must mean then that EM forces (and other equations?) must
> somehow be able to measure distances "outside" of this distorted and
> gobbled up space? There must be an external "real" space that is somehow
> related to the distored spacetime by the distribution of mass around.
No, there's no need for any "meta-space". In the vicinity of any mass,
EM forces still propagate according to Maxwell's wave equations through
whatever space is there at the very moment the wavefront traverses it.
Which is exactly why light appears to "bend" around massive objects.
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>> If gravity (or rather, mass) causes space to contract and get gobbled
>> up, this must mean then that EM forces (and other equations?) must
>> somehow be able to measure distances "outside" of this distorted and
>> gobbled up space? There must be an external "real" space that is somehow
>> related to the distored spacetime by the distribution of mass around.
>
> No, there's no need for any "meta-space". In the vicinity of any mass,
> EM forces still propagate according to Maxwell's wave equations through
> whatever space is there at the very moment the wavefront traverses it.
I suppose that the EM waves travel very much faster than the space is
getting distorted, so in terms of the "reaction time" of atoms being
able to move to keep up it is no problem at all. Until you get to a
black hole :-)
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On 10/19/2015 3:06 PM, clipka wrote:
> and Earth's surface
> accelerating radially from its center at 9.81 m/s^2.
I know it is the psilocybin mushroom season but I thought I was the old
hippy who had taken mind bending substances (in the past, I might add in
case PC Plod is listening).
You have lost it dear friend.
You have lost it.
--
Regards
Stephen
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Am 19.10.2015 um 19:44 schrieb Stephen:
> On 10/19/2015 3:06 PM, clipka wrote:
>> and Earth's surface
>> accelerating radially from its center at 9.81 m/s^2.
>
> I know it is the psilocybin mushroom season but I thought I was the old
> hippy who had taken mind bending substances (in the past, I might add in
> case PC Plod is listening).
> You have lost it dear friend.
> You have lost it.
Just following Einstein's train of thoughts. No shrooms growing there.
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On 10/19/2015 10:06 PM, clipka wrote:
> Am 19.10.2015 um 19:44 schrieb Stephen:
>> On 10/19/2015 3:06 PM, clipka wrote:
>>> and Earth's surface
>>> accelerating radially from its center at 9.81 m/s^2.
>>
>> I know it is the psilocybin mushroom season but I thought I was the old
>> hippy who had taken mind bending substances (in the past, I might add in
>> case PC Plod is listening).
>> You have lost it dear friend.
>> You have lost it.
>
> Just following Einstein's train of thoughts. No shrooms growing there.
>
Pity cause they would go well with the potatoes in my ears. :-)
> Whatever frame of reference you choose - if it is truly inertial, you'll
> always find the apple (while airborne) moving at constant velocity (or
> remaining at rest, which is a special case thereof),
Assuming that you are not trying to wind me up.
What are your reasons for saying that? If your frame of reference was
the apple I would agree with you. But I was talking about a frame of
reference separate from both of the objects.
> and Earth's surface
> accelerating radially from its center at 9.81 m/s^2.
To me that reads that the Earth's surface (and volume) is expanding.
Something I personally haven't noticed.
Since we are talking about speeds of metres per second I assume we can
dismiss any relativistic effects.
Can you explain why a force of one Newton acting on a mass of 5.97E+24
Kg can produce an acceleration of 9.81 m/s^2?
I make it 0.000000000000000000000000167504 m/s^2
> (As long as you
> ignore aerodynamic drag and remain sufficiently close to Earth's surface
> and the apple, that is.)
Granted.
--
Regards
Stephen
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Am 20.10.2015 um 17:24 schrieb Stephen:
>> Whatever frame of reference you choose - if it is truly inertial, you'll
>> always find the apple (while airborne) moving at constant velocity (or
>> remaining at rest, which is a special case thereof),
>
> Assuming that you are not trying to wind me up.
> What are your reasons for saying that? If your frame of reference was
> the apple I would agree with you. But I was talking about a frame of
> reference separate from both of the objects.
Okay, so you agree that the dropping apple's frame of reference is an
inertial one.
Then by definition of what constitutes an inertial frame of reference,
all (sufficiently local) frames of reference in which the apple appears
to be moving at constant speed are inertial, while all in which the
apple appears to be accelerating are non-inertial.
Now no matter what frame of reference you choose, you'll find that
Earth's surface and the apple appear to be accelerating towards each
other; thus any frame of reference in which the apple isn't
accelerating, must have Earth's surface accelerating towards it instead.
>> and Earth's surface
>> accelerating radially from its center at 9.81 m/s^2.
>
> To me that reads that the Earth's surface (and volume) is expanding.
> Something I personally haven't noticed.
That's because it is in equilibrium with the collapse of space.
What you should be able to notice is you being subject to acceleration:
If someone locked you in an elevator cabin, you couldn't tell the
difference between being "stationary" on Earth's surface, and being
subject to an acceleration of 9.81 m/s^2 in deep space.
Because there is no difference.
> Since we are talking about speeds of metres per second I assume we can
> dismiss any relativistic effects.
Strictly speaking we can't, as the whole thing /is/ a relativistic effect.
> Can you explain why a force of one Newton acting on a mass of 5.97E+24
> Kg can produce an acceleration of 9.81 m/s^2?
No, but why should I?
- Not all of Earth's mass is accelerating at 9.81 m/s^2; the deeper you
go, the smaller the acceration, until it drops to zero at Earth's center.
- I have no idea where you got the one Newton from. The actual force
pushing Earth's surface outward is about _ten_ Newton _per kg of surface
mass_. More precisely it is 9.81 N/kg. Or 9.81 m/s^2.
Yup, that's a mind-bogglingly huge total force acting on Earth's mass.
But electromagnetic forces between atoms under pressure /are/
mind-bogglingly huge.
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On 10/20/2015 10:45 PM, clipka wrote:
> Am 20.10.2015 um 17:24 schrieb Stephen:
>
>>> Whatever frame of reference you choose - if it is truly inertial, you'll
>>> always find the apple (while airborne) moving at constant velocity (or
>>> remaining at rest, which is a special case thereof),
>>
>> Assuming that you are not trying to wind me up.
>> What are your reasons for saying that? If your frame of reference was
>> the apple I would agree with you. But I was talking about a frame of
>> reference separate from both of the objects.
>
> Okay, so you agree that the dropping apple's frame of reference is an
> inertial one.
>
No, I don't. I selected an observational frame of reference where I
could observe both objects, a few posts back.
> Then by definition of what constitutes an inertial frame of reference,
> all (sufficiently local) frames of reference in which the apple appears
> to be moving at constant speed are inertial, while all in which the
> apple appears to be accelerating are non-inertial.
>
I am having difficulty with that. My chosen frame of reference is
inertial and both the apple and Earth are accelerating. Albeit a very
small acceleration in the case of the Earth.
> Now no matter what frame of reference you choose, you'll find that
> Earth's surface and the apple appear to be accelerating towards each
> other; thus any frame of reference in which the apple isn't
> accelerating, must have Earth's surface accelerating towards it instead.
>
I agree with that.
>>> and Earth's surface
>>> accelerating radially from its center at 9.81 m/s^2.
>>
>> To me that reads that the Earth's surface (and volume) is expanding.
>> Something I personally haven't noticed.
>
No. I read radially as meaning "Radiating from or converging to a common
centre." Not along a radius.
A bit of a slap in the face with a wet fish. *
Misunderstanding understood.
> That's because it is in equilibrium with the collapse of space.
>
> What you should be able to notice is you being subject to acceleration:
> If someone locked you in an elevator cabin, you couldn't tell the
> difference between being "stationary" on Earth's surface, and being
> subject to an acceleration of 9.81 m/s^2 in deep space.
>
> Because there is no difference.
>
With a pendulum you could but who am I to teach my grandmother to suck
eggs when it comes to nitpicking. ;-)
>> Since we are talking about speeds of metres per second I assume we can
>> dismiss any relativistic effects.
>
> Strictly speaking we can't, as the whole thing /is/ a relativistic effect.
>
>> Can you explain why a force of one Newton acting on a mass of 5.97E+24
>> Kg can produce an acceleration of 9.81 m/s^2?
>
> No, but why should I?
>
Because I asked nicely.
> - Not all of Earth's mass is accelerating at 9.81 m/s^2; the deeper you
> go, the smaller the acceration, until it drops to zero at Earth's center.
>
Great! a mass of round about 100 grammes distorts the Earth's surface.
> - I have no idea where you got the one Newton from. The actual force
> pushing Earth's surface outward is about _ten_ Newton _per kg of surface
> mass_. More precisely it is 9.81 N/kg. Or 9.81 m/s^2.
>
Rough and ready:
http://hypertextbook.com/facts/2004/WaiWingLeung.shtml
> Yup, that's a mind-bogglingly huge total force acting on Earth's mass.
> But electromagnetic forces between atoms under pressure /are/
> mind-bogglingly huge.
>
Personally I prefer to pick my frames to make sense in the real world.
If you can't hit it with a hammer or build a bridge out of it. Then it
is just an interesting thought.
*
I found this Wiki entry
https://en.wikipedia.org/wiki/Wikipedia:Whacking_with_a_wet_trout
--
Regards
Stephen
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Am 21.10.2015 um 05:34 schrieb Stephen:
> I am having difficulty with that. My chosen frame of reference is
> inertial and both the apple and Earth are accelerating. Albeit a very
> small acceleration in the case of the Earth.
Then tell me, how do you know that your frame of reference is inertial?
Also note that you need to choose a frame of reference sufficiently
local to both Earth's surface and the apple, otherwise your frame of
reference will distort over time, which you'd then have to factor back
in to judge changes of distance over time.
Maybe one of the fundamental hurdles you need to take is this: Space
distorts over time, and changes in relative position do not necessarily
require an absolute movement of the objects involved.
>> What you should be able to notice is you being subject to acceleration:
>> If someone locked you in an elevator cabin, you couldn't tell the
>> difference between being "stationary" on Earth's surface, and being
>> subject to an acceleration of 9.81 m/s^2 in deep space.
>>
>> Because there is no difference.
>
> With a pendulum you could but who am I to teach my grandmother to suck
> eggs when it comes to nitpicking. ;-)
No, as a matter of pure fact you couldn't (the pendulum thing; I don't
know about your grandmother and the eggs). Not unless you know something
that would win you the Nobel prize :)
>>> Since we are talking about speeds of metres per second I assume we can
>>> dismiss any relativistic effects.
>>
>> Strictly speaking we can't, as the whole thing /is/ a relativistic
>> effect.
>>
>>> Can you explain why a force of one Newton acting on a mass of 5.97E+24
>>> Kg can produce an acceleration of 9.81 m/s^2?
>>
>> No, but why should I?
>
> Because I asked nicely.
>
>> - Not all of Earth's mass is accelerating at 9.81 m/s^2; the deeper you
>> go, the smaller the acceration, until it drops to zero at Earth's center.
>
> Great! a mass of round about 100 grammes distorts the Earth's surface.
Well, /any/ mass distorts the Earth's surface...
>> - I have no idea where you got the one Newton from. The actual force
>> pushing Earth's surface outward is about _ten_ Newton _per kg of surface
>> mass_. More precisely it is 9.81 N/kg. Or 9.81 m/s^2.
>>
> Rough and ready:
> http://hypertextbook.com/facts/2004/WaiWingLeung.shtml
Ah, I see - so I understand that you're still obsessed with the apple
having anything to do with the whole smash, when in fact its effects are
(as you correctly note) negligible. It doesn't /cause/ the distortion of
space - that's by far and large Earth's job - its sole purpose is to
help /visualize/ it, by providing an intertial frame of reference.
> Personally I prefer to pick my frames to make sense in the real world.
> If you can't hit it with a hammer or build a bridge out of it. Then it
> is just an interesting thought.
Well, then you're not the target audience of my post, so move along,
there is nothing for you to see here ;)
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> Which is exactly why light appears to "bend" around massive objects.
How does the theory deal with the light potentially having to go faster
than the speed of light (for example when the photons are aimed straight
at the centre of a massive object from afar)? If light always goes at
"c" relative to the local space, and the space is getting distorted,
this would appear to make the light go faster than "c" no?
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Am 21.10.2015 um 12:01 schrieb scott:
>> Which is exactly why light appears to "bend" around massive objects.
>
> How does the theory deal with the light potentially having to go faster
> than the speed of light (for example when the photons are aimed straight
> at the centre of a massive object from afar)? If light always goes at
> "c" relative to the local space, and the space is getting distorted,
> this would appear to make the light go faster than "c" no?
No, it would just reduce the distance the light needs to go.
(Also, mass tampers not only with space but also with time.)
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>> How does the theory deal with the light potentially having to go faster
>> than the speed of light (for example when the photons are aimed straight
>> at the centre of a massive object from afar)? If light always goes at
>> "c" relative to the local space, and the space is getting distorted,
>> this would appear to make the light go faster than "c" no?
>
> No, it would just reduce the distance the light needs to go.
>
> (Also, mass tampers not only with space but also with time.)
Just when you think you understand it! I thought I just had a vague
recollection of once reading a proposal for faster-than-light travel,
whereby space was distorted infront of and behind the object moving in a
certain way. But maybe it was Asimov that wrote it :-)
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Am 21.10.2015 um 17:04 schrieb Stephen:
I give up!
You win.
You have ground me down.
The best team won.
I owe you a drink.
(I'm just saying that you know. I am still right.) ;-)
--
Regards
Stephen
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Am 21.10.2015 um 18:30 schrieb Stephen:
> Am 21.10.2015 um 17:04 schrieb Stephen:
>
> I give up!
> You win.
> You have ground me down.
> The best team won.
> I owe you a drink.
Here I was trying to convince you, and all I got is this lousy T-shirt...
> (I'm just saying that you know. I am still right.) ;-)
Of course. Aren't we all? :)
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Le 21/10/2015 17:00, scott a écrit :
>>> How does the theory deal with the light potentially having to go faster
>>> than the speed of light (for example when the photons are aimed straight
>>> at the centre of a massive object from afar)? If light always goes at
>>> "c" relative to the local space, and the space is getting distorted,
>>> this would appear to make the light go faster than "c" no?
presence of mass do not shorten the "distance". rather the opposite.
Think of it like liquid static water. presence of mass is adding jelly.
Now swim your way... it might be faster to go around the jelly than
going through it... even if the road would be pi/2 longer, at least for
some dense jelly spots.
btw, there is known experiment about travelling faster than light in a
medium (is that local space ?): it is possible, and it results in
Cherenkov radiation.
the void has the ior of 1, to go faster than light in void, you just
need to find "something" with an ior less than 1. The problem is
"just"... is there such white crow ?
>>
>> No, it would just reduce the distance the light needs to go.
>>
>> (Also, mass tampers not only with space but also with time.)
>
> Just when you think you understand it! I thought I just had a vague
> recollection of once reading a proposal for faster-than-light travel,
> whereby space was distorted infront of and behind the object moving in a
> certain way. But maybe it was Asimov that wrote it :-)
>
Might be tied to Roddenberry. You do not violate the rules of the speed
light limit in the fabric of the universe when you warp the fabric
instead of moving.
the saga ends with warp travel being limited due to the breaking of the
fabric caused by all the warping.
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> btw, there is known experiment about travelling faster than light in a
> medium (is that local space ?): it is possible, and it results in
> Cherenkov radiation.
>
> the void has the ior of 1, to go faster than light in void, you just
> need to find "something" with an ior less than 1. The problem is
> "just"... is there such white crow ?
See my other thread "Random answer..." - AIUI ior less than one doesn't
actually mean the light travels faster than "c" through it, just the
peaks of the waves appear to move faster than "c" through it. It's
relatively easy to convince yourself that if the medium is generating
waves at the correct phase offset from the original source, when
combined with the source wave, it looks like the wave is going faster
than light through the medium.
>> Just when you think you understand it! I thought I just had a vague
>> recollection of once reading a proposal for faster-than-light travel,
>> whereby space was distorted infront of and behind the object moving in a
>> certain way. But maybe it was Asimov that wrote it :-)
>>
> Might be tied to Roddenberry. You do not violate the rules of the speed
> light limit in the fabric of the universe when you warp the fabric
> instead of moving.
>
> the saga ends with warp travel being limited due to the breaking of the
> fabric caused by all the warping.
OK it apparently has a name, but it seems unclear whether it is
physically possible to ever construct:
https://en.wikipedia.org/wiki/Alcubierre_drive
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On 10/21/2015 10:50 PM, clipka wrote:
> Am 21.10.2015 um 18:30 schrieb Stephen:
>> Am 21.10.2015 um 17:04 schrieb Stephen:
>>
>> I give up!
>> You win.
>> You have ground me down.
>> The best team won.
>> I owe you a drink.
>
> Here I was trying to convince you, and all I got is this lousy T-shirt...
>
A lousy T-shirt! (said in the voice of Dame Edith Evans.
https://www.youtube.com/watch?v=oyuoUwxCLMs )
I offered to by you a drink, extending the cup of friendship. It might
even be possible to twist Dr. John's arm up his back to buy you the
second round.
I did understand you but don't agree with your conclusions.
>> (I'm just saying that you know. I am still right.) ;-)
>
> Of course. Aren't we all? :)
>
No. I was wrong once.
1972 if memory serves.
--
Regards
Stephen
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Am 22.10.2015 um 17:44 schrieb Stephen:
> On 10/21/2015 10:50 PM, clipka wrote:
>> Am 21.10.2015 um 18:30 schrieb Stephen:
>>> Am 21.10.2015 um 17:04 schrieb Stephen:
>>>
>>> I give up!
>>> You win.
>>> You have ground me down.
>>> The best team won.
>>> I owe you a drink.
>>
>> Here I was trying to convince you, and all I got is this lousy T-shirt...
>>
>
> A lousy T-shirt! (said in the voice of Dame Edith Evans.
> https://www.youtube.com/watch?v=oyuoUwxCLMs )
>
> I offered to by you a drink, extending the cup of friendship. It might
> even be possible to twist Dr. John's arm up his back to buy you the
> second round.
Too obvious: Brits + drink + cup = tea, certainly destined to end up on
my shirt while wrestling with Dr. John.
T-shirt, like I said. Lousy.
> I did understand you but don't agree with your conclusions.
>
>>> (I'm just saying that you know. I am still right.) ;-)
>>
>> Of course. Aren't we all? :)
>
> No. I was wrong once.
> 1972 if memory serves.
Nah, you're surely wrong there.
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On 10/22/2015 6:47 PM, clipka wrote:
> Am 22.10.2015 um 17:44 schrieb Stephen:
>> I offered to by you a drink, extending the cup of friendship. It might
>> even be possible to twist Dr. John's arm up his back to buy you the
>> second round.
>
> Too obvious: Brits + drink + cup = tea,
Cup? Nah! we drink straight from the bottle. Nae point in dirtying a glass.
> certainly destined to end up on
> my shirt while wrestling with Dr. John.
>
No worries. John prefers naked mud wrestling but don't worry. He is not
very good at it. ;-)
> T-shirt, like I said. Lousy.
>
>
As you will. I prefer woad.
>> I did understand you but don't agree with your conclusions.
>>
>>>> (I'm just saying that you know. I am still right.) ;-)
>>>
>>> Of course. Aren't we all? :)
>>
>> No. I was wrong once.
>> 1972 if memory serves.
>
> Nah, you're surely wrong there.
>
Don't tell my wife. She thinks that is when we got married.
--
Regards
Stephen
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