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Darren New wrote:
> Name energy that isn't in the form of mass?
> Then explain what E=mc^2 means.
Light isn't in the form of mass. Sound isn't in the form of mass.
Electricity isn't in the form of mass. Magnetism isn't in the form of
mass. And so forth.
E=mc^2 means that the amount of energy stored in a given mass can be
determined by multiplying the mass by the speed of light squared. It's
like...a bank account. The number in the bank's computer that says how
much is in the bank account is not the same thing as however many
physical dollar bills and change, but they are treated as equivalent.
--
Tim Cook
http://home.bellsouth.net/p/PWP-empyrean
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Tim Cook wrote:
> Darren New wrote:
>> Name energy that isn't in the form of mass?
>> Then explain what E=mc^2 means.
>
> Light isn't in the form of mass.
Yes it is. Photons have mass. Indeed, the reason they go the speed of
light is (sloppily speaking) that they are *all* energy, so they *have*
to go the speed of light just to have mass to hold the energy.
> Sound isn't in the form of mass.
The atoms move to make sound. Sound is kinetic energy, which is mass due
to relativistic movement.
> Electricity isn't in the form of mass.
Electrons move, hence kinetic energy, hence mass.
> Magnetism isn't in the form of mass.
Magnetism consists of photons. Photons have mass.
> E=mc^2 means that the amount of energy stored in a given mass can be
> determined by multiplying the mass by the speed of light squared.
Equally, it says that the amount of energy can be determined by
multiplying the amount of mass by the speed of light squared. That's an
equal sign there. That's how relativity works.
Where does the kinetic energy in a moving asteroid go if I accelerate my
spaceship up to the same speed? Does the stationary observer see more
energy than the observer moving at the same speed? Wouldn't that mean
that energy can be created and destroyed at will, just by moving the
observer without changing the experiment? Do you understand why leaving
a gravity well makes you heavier?
I know what you're trying to say. You're trying to say that there is
energy that's not the equivalent of mass, and that E=mc^2 only applies
to mass, not energy. That's incorrect. Intuitive, but incorrect. Really
and truly. That's why it took so long to be accepted.
--
Darren New / San Diego, CA, USA (PST)
Remember the good old days, when we
used to complain about cryptography
being export-restricted?
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Darren New wrote:
> Tim Cook wrote:
>> Darren New wrote:
>>> Name energy that isn't in the form of mass?
>>> Then explain what E=mc^2 means.
>>
>> Light isn't in the form of mass.
>
> Yes it is. Photons have mass. Indeed, the reason they go the speed of
> light is (sloppily speaking) that they are *all* energy, so they *have*
> to go the speed of light just to have mass to hold the energy.
>
>> Sound isn't in the form of mass.
>
> The atoms move to make sound. Sound is kinetic energy, which is mass due
> to relativistic movement.
>
>> Electricity isn't in the form of mass.
>
> Electrons move, hence kinetic energy, hence mass.
>
>> Magnetism isn't in the form of mass.
>
> Magnetism consists of photons. Photons have mass.
>
>> E=mc^2 means that the amount of energy stored in a given mass can be
>> determined by multiplying the mass by the speed of light squared.
>
> Equally, it says that the amount of energy can be determined by
> multiplying the amount of mass by the speed of light squared. That's an
> equal sign there. That's how relativity works.
>
> Where does the kinetic energy in a moving asteroid go if I accelerate my
> spaceship up to the same speed? Does the stationary observer see more
> energy than the observer moving at the same speed? Wouldn't that mean
> that energy can be created and destroyed at will, just by moving the
> observer without changing the experiment? Do you understand why leaving
> a gravity well makes you heavier?
>
> I know what you're trying to say. You're trying to say that there is
> energy that's not the equivalent of mass, and that E=mc^2 only applies
> to mass, not energy.
No, I'm trying to say that...mass is a specific form of energy, as are
all those other forms of energy, but they aren't each other. Sound is
not light, because it has defining properties that are different.
Otherwise we'd just call everything 'energy'. It's like...number sets.
Energy is the set of all numbers, mass is the set of all positive
integers, light is the set of all negative primes, and so forth. You
can convert one to another with a bit of fiddling, but they aren't
congruent subsets.
--
Tim Cook
http://home.bellsouth.net/p/PWP-empyrean
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Tim Cook wrote:
> Otherwise we'd just call everything 'energy'.
Those who understand how it works *do* call everything "energy". Before
people understood what "energy" is, they called different aspects of the
same thing "energy". Like asking whether the elephant is a rope, or a
tree, or a wall.
People used to think width != height != length != duration, too, but
that isn't right either, and they're all aspects of the same thing.
That's why they call it "spacetime" instead of "space" and "time".
Asking "can mass be converted to different kinds of energy" is like
asking "can different kinds of distances be converted to other kinds of
distances?"
> Energy is the set of all numbers, mass is the set of all positive
> integers, light is the set of all negative primes, and so forth.
No. That's what the = sign means. Heat energy is stored as mass. Nuclear
energy is stored as mass. Kinetic energy is stored as mass. Energy is
mass, mass is energy. All mass is energy, all energy is mass. There
isn't some energy-that-is-mass and some energy-that-isn't-mass and you
can convert between them, because then energy wouldn't be conserved in a
closed system, and an experiment you do here would have different
results than an experiment you do there.
It's like saying "how do I convert my word-processor into a number
cruncher?" You rearrange the patterns of bits. But there's no separate
word processor or number cruncher. It's the same parts (i.e., electrons)
in different places.
Put it this way: Do you believe in the conservation of energy? That
energy cannot be created or destroyed in a closed system? If so, where
does the extra mass come from when you accelerate something close to
relativistic speeds? Where does the energy you used to lift a brick out
of a gravity field go? (I.e., what *is* "potential energy" beyond just
words?)
There's no such thing as "energy" beyond a mathematical concept. The
different kinds of energy are different ways of measuring the same
thing. They are ways of calculating patterns of mass.
In exactly the same way, infrared light is ultraviolet light is gamma
radiation is radio waves. Can you convert infrared light to ultraviolet
light? Sure. You don't even have to do anything to the light. Just start
moving real fast towards the source of the light. They are *identical*,
and asking whether it's possible to convert photons to light waves is
unanswerable, because they really are in every respect the same thing
looked at with two different mathematical mechanisms.
Can you explain what kinetic energy *is*? Can you explain why an object
gains mass as it leaves a gravitational field, or why it seems heavier
to an observer moving relative to it compared to an observer stationary
with respect to it? Can you explain where the kinetic energy of a
falling brick comes from if it started at rest in a gravity field?
--
Darren New / San Diego, CA, USA (PST)
Remember the good old days, when we
used to complain about cryptography
being export-restricted?
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Darren New wrote:
> Asking "can mass be converted to different kinds of energy" is like
> asking "can different kinds of distances be converted to other kinds of
> distances?"
The answer is, simply, 'yes'. Metric distances can be converted to
imperial distances. A few grams of Uranium can be converted to a
heaping mass of heat, light, smoke, radiation, et cetera, but is not
inherently those things.
> No. That's what the = sign means. Heat energy is stored as mass. Nuclear
> energy is stored as mass. Kinetic energy is stored as mass. Energy is
> mass, mass is energy. All mass is energy, all energy is mass.
The important bit of this paragraph is "is stored as". That's a vital
difference.
> It's like saying "how do I convert my word-processor into a number
> cruncher?" You rearrange the patterns of bits. But there's no separate
> word processor or number cruncher. It's the same parts (i.e., electrons)
> in different places.
But it has a different function and appearance. A number cruncher is
not a word processor, in terms of how it is used.
> Put it this way: Do you believe in the conservation of energy? That
> energy cannot be created or destroyed in a closed system? If so, where
> does the extra mass come from when you accelerate something close to
> relativistic speeds? Where does the energy you used to lift a brick out
> of a gravity field go? (I.e., what *is* "potential energy" beyond just
> words?)
I remember reading something along the lines of 'that's what time is'.
Put simply, an object at rest moves through the 'time' dimension at the
speed of light, which is why time appears to slow to nothing for the
object as it approaches c. So that's what potential energy is. Time.
> There's no such thing as "energy" beyond a mathematical concept. The
> different kinds of energy are different ways of measuring the same
> thing. They are ways of calculating patterns of mass.
But they're more than just a mathematical concept, because they are
tangible and can be perceived.
> Can you convert infrared light to ultraviolet
> light? Sure. You don't even have to do anything to the light. Just start
> moving real fast towards the source of the light.
But then you are doing something to the light there; you're changing
your point of reference. ;)
--
Tim Cook
http://home.bellsouth.net/p/PWP-empyrean
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Tim Cook wrote:
> Darren New wrote:
>> Asking "can mass be converted to different kinds of energy" is like
>> asking "can different kinds of distances be converted to other kinds
>> of distances?"
>
> The answer is, simply, 'yes'. Metric distances can be converted to
> imperial distances.
But that's only changing what you call it. That's not changing what it
is. Changing the axis you use when measuring a vector doesn't change
where the vector is.
> A few grams of Uranium can be converted to a
> heaping mass of heat, light, smoke, radiation, et cetera, but is not
> inherently those things.
Uranium isn't radiation, no. But radiation is mass. Asking if uranium
can be turned into different kinds of radiation can be answered "yes".
>> No. That's what the = sign means. Heat energy is stored as mass.
>> Nuclear energy is stored as mass. Kinetic energy is stored as mass.
>> Energy is mass, mass is energy. All mass is energy, all energy is mass.
>
> The important bit of this paragraph is "is stored as". That's a vital
> difference.
No, it's not. It's the same thing, measured a different way. By "is
stored as" I meant it's the same thing - that all energy is in the mass,
that's where it *is*, that's where it *lives* so to speak. There's not a
pile of energy, and a pile of mass, that you convert between, any more
than a vector has an amount of high and an amount of wide that you
convert between by rotating your reference axis. The vector is what it
is (like the mass), and if you measure it in one direction, you get a
little height and a lot of width (like a little kinetic energy and a lot
of potential energy), and if you look at it a different way, you get a
lot of height and a little width. But asking whether the vector itself
can be converted into different kinds of heights and widths is a
category error, because the height and width are "stored as" the vector.
That's why people kept discovering new "forms" of energy, and then over
the years realized they're all the same sort of thing, with heat being
kinetic energy of atoms, and chemical energy being electrostatic energy
of their valence electrons, and so on.
>> It's like saying "how do I convert my word-processor into a number
>> cruncher?" You rearrange the patterns of bits. But there's no
>> separate word processor or number cruncher. It's the same parts (i.e.,
>> electrons) in different places.
>
> But it has a different function and appearance. A number cruncher is
> not a word processor, in terms of how it is used.
But that's how you look at it, not what it inherently is. It's how you
measure the functionality. They're both the same computer. Asking if
mass can be turned into different kinds of energy is asking if the
computer itself (while running both programs) can be turned into a word
processor or a number cruncher. It *is* both those things already,
depending on how you care to measure it. Exactly: Mass is energy,
depending on how it's used. Different forms of energy are different
depending on how they're used, not what they are. It's a mental
category, unrelated to reality. A plant in your garden is only a weed if
you don't want it there.
You can turn mass of one type into mass of a different type. You can
turn neutrons into photons. But it's all mass, and they'll all have the
same total mass when you're done. If you want to speak imprecisely, and
ignore the energy that is rest mass, then yes, you can turn *rest* mass
into energy. But that isn't how physics actually works, any more than
Newton had the laws of motion precisely right. That one is sloppy in
ones definition of "energy" doesn't mean the precise person is
incorrect. :-)
>> Put it this way: Do you believe in the conservation of energy? That
>> energy cannot be created or destroyed in a closed system? If so, where
>> does the extra mass come from when you accelerate something close to
>> relativistic speeds? Where does the energy you used to lift a brick
>> out of a gravity field go? (I.e., what *is* "potential energy" beyond
>> just words?)
>
> I remember reading something along the lines of 'that's what time is'.
> Put simply, an object at rest moves through the 'time' dimension at the
> speed of light, which is why time appears to slow to nothing for the
> object as it approaches c.
Uh, sort of. Not really. That's one way of looking at it,
mathematically speaking. Like changing the axes you use to look at a
vector, and saying "the reason it gets higher is it gets less wide."
> So that's what potential energy is. Time.
Errr, no. Quite the opposite.
Anyway, you didn't answer the question. Do you believe in the
conservation of energy. If so, where does the extra mass come from?
>> There's no such thing as "energy" beyond a mathematical concept. The
>> different kinds of energy are different ways of measuring the same
>> thing. They are ways of calculating patterns of mass.
>
> But they're more than just a mathematical concept, because they are
> tangible and can be perceived.
You're perceiving the interaction of the mass against other mass as
mediated primarily by photon exchange between electrons. They're no more
different than meauring heat in kelvins and heat in farenheit.
This is exactly my point: Energy *isn't* tangible and *can't* be
perceived. Tell me how you perceive potential energy? How you perceive
kinetic energy? Can you look at a lump of coal and perceive the
chemical bond energy in it? No, you have to turn them into some other
form of energy in some other piece of mass for which we have measuring
devices.
>> Can you convert infrared light to ultraviolet light? Sure. You don't
>> even have to do anything to the light. Just start moving real fast
>> towards the source of the light.
>
> But then you are doing something to the light there; you're changing
> your point of reference. ;)
That's my point. It's your point of reference that says mass is
different from energy. If you're moving fast relative to the rock, it
has lots of energy. If you're not, it doesn't. Did the rock change?
--
Darren New / San Diego, CA, USA (PST)
Remember the good old days, when we
used to complain about cryptography
being export-restricted?
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Darren New wrote:
> Warp wrote:
>> Darren New <dne### [at] san rrcom> wrote:
[snip]
The trouble with this discussion is that it started off with Newtonian
mechanics, and now you're arguing over the finer wording of some of the
consequences of special relativity. And while you're technically right
about the equivalence, you can't really say that a photon has mass
without being more specific - it can have the mass associated with its
energy, but must have no *inertial* mass or relativity doesn't work at all.
Warp was trying to clarify his understanding of momentum (which can be a
tricky concept to separate from energy if you've not learned physics to
quite a high level) and this isn't likely to help him. :-)
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On Mon, 29 Oct 2007 15:17:18 -0500, Warp wrote:
> Then wikipedia is horribly wrong, I suppose.
Wikipedia isn't always right....
Jim
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Warp nous apporta ses lumieres en ce 2007/10/29 16:17:
> Darren New <dne### [at] sanrrcom> wrote:
>> There is no "other form" of energy. All energy and mass are the same
>> thing. To ask whether mass can be converted to other forms of energy is
>> meaningless.
>
> Then wikipedia is horribly wrong, I suppose.
>
> http://en.wikipedia.org/wiki/Energy_conversion
>
No.
Energy stays contant, it's only it's "manifestation" that change, or *how* we
perceive it that change.
--
Alain
-------------------------------------------------
My wife is such a bad cook, in my house we pray after the meal.
Rodney Dangerfield
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Tim Cook nous apporta ses lumieres en ce 2007/10/29 23:29:
> Darren New wrote:
>> Tim Cook wrote:
>>> Darren New wrote:
>>>> Name energy that isn't in the form of mass?
>>>> Then explain what E=mc^2 means.
>>>
>>> Light isn't in the form of mass.
>>
>> Yes it is. Photons have mass. Indeed, the reason they go the speed of
>> light is (sloppily speaking) that they are *all* energy, so they
>> *have* to go the speed of light just to have mass to hold the energy.
>>
>>> Sound isn't in the form of mass.
>>
>> The atoms move to make sound. Sound is kinetic energy, which is mass
>> due to relativistic movement.
>>
>>> Electricity isn't in the form of mass.
>>
>> Electrons move, hence kinetic energy, hence mass.
>>
>>> Magnetism isn't in the form of mass.
>>
>> Magnetism consists of photons. Photons have mass.
>>
>>> E=mc^2 means that the amount of energy stored in a given mass can be
>>> determined by multiplying the mass by the speed of light squared.
>>
>> Equally, it says that the amount of energy can be determined by
>> multiplying the amount of mass by the speed of light squared. That's
>> an equal sign there. That's how relativity works.
>>
>> Where does the kinetic energy in a moving asteroid go if I accelerate
>> my spaceship up to the same speed? Does the stationary observer see
>> more energy than the observer moving at the same speed? Wouldn't that
>> mean that energy can be created and destroyed at will, just by moving
>> the observer without changing the experiment? Do you understand why
>> leaving a gravity well makes you heavier?
>>
>> I know what you're trying to say. You're trying to say that there is
>> energy that's not the equivalent of mass, and that E=mc^2 only applies
>> to mass, not energy.
>
> No, I'm trying to say that...mass is a specific form of energy, as are
> all those other forms of energy, but they aren't each other. Sound is
> not light, because it has defining properties that are different.
> Otherwise we'd just call everything 'energy'. It's like...number sets.
> Energy is the set of all numbers, mass is the set of all positive
> integers, light is the set of all negative primes, and so forth. You
> can convert one to another with a bit of fiddling, but they aren't
> congruent subsets.
>
Energy IS mass! It's just that in everyday experiance, that mass is aparently to
small to be perceived.
Take an electron, accelerate it suficiently, and you can make it's mass grow to
rival that of a TRAIN or even a SUPER TANKER! Where does this mass increase
comes from? Uniquely from the kynetic energy of that speeding electron.
Now, take that electron and make it collide with any other particle. You will
get a HUGE gamma burst. Gamma radiation is light. The kynetic energy mass gets
transformed into light. And remember: light can push objects. It's just that
this push is normaly to small for you to notice, but it can easily be
demonstrated with a very simple experiment.
Take an empty globe of glass, place a needle holding a light rotor made from a
glass axis and holding 3 or 4 blades, white on one side, black on the other.
Place the rotor on the needle. Remove all air from the globe. Have ANY light
shining on that rotor, even a candle light, and the rotor will spinn. That
experiment is over 100 years old!
--
Alain
-------------------------------------------------
An unbreakable toy is useful for breaking other toys.
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