# Undefined Time

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If you travel at c, time is undefined. Mass is also. What is undefiend mass/time? Does it mean that time/mass doesn't exist or does it mean something else?

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It means you don't travel at c. There are no frames that travel at c or greater relative to any other inertial frame.

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Could it be possible that time and space are equivilent? Mass and energy are equivilent: why shouldn't shouldn't this basic pattern be extended to the other major constituent of nature. It has always bothered me that it takes a great deal of energy to accelerate mass to relativistic speeds, but an atom's photons seem to leave their atomic system with the only energy loss to the system being the energy expressed as the photons frequency. If time and space were equivilent and the temporal flow were C, wouldn't it be possible that except for oscillations that we detect as wave frequency, the photons simply stop temporaly and we temporaly run into them at C?

aguy2

"There is a relatively high probability that we and the universe around us are involved in an ongoing, staged process of self-creation; wherein and whereby the creator of us and the universe around is attempting to create itself."

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Could it be possible that time and space are equivilent?

They are (at least in the sense that energy and momentum are equivalent)! This was one of the main points of Special Relativity: a Lorentz transformation is (sort-of) a rotation in space-time. the only real difference between space and time in fundamental physics is that the time entry in the metric has the opposite sign, ie. a distance in space-time is measured as:

ds2 = dt2 - dx2 - dy2 - dz2

Energy and mass, on the other hand, are not equivalent. One can be changed into the other, but they are not the same thing.

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Mass and energy are equivilent

mass and energy aren't equivilent. $E=mc^2$, not $E=m$

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I think he probably means 'interchangeable'.

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If it wa sonly the factor of c^2 we had to worry about then we would say thta mass and enrgy were equivalent, but it's the fact that the total energy of an object in some frame is not depedent only on it's mass.

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Mass and energy aren't equivilent.

If it wa sonly the factor of C^2 we had to worry about then we would say thta mass and enrgy were equivalent, but it's the fact that the total energy of an object in some frame is not dependent only on its mass.

American Heritage Dictionary

mass-energy equivalence: noun, the physical principle that a measured quantity of energy is equivalent to a measured quantity of mass. The equivalence is expressed by Einsteins equation E=MC2.

aguy2

"There is a relatively high probability that we and the universe around us could very well be involved in an ongoing,staged process of self-creation: wherein and whereby the creator of us and the universe around us is attempting to create itself."

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"There is a relatively high probability that we and the universe around us could very well be involved in an ongoing,staged process of self-creation: wherein and whereby the creator of us and the universe around us is attempting to create itself."

huh?

back to topic: since time, length, and mass are undefined at c, does that mean that you are non-existant?

at ftl speeds, your mass, length, and time are imaginary, so i guess that means you aren't real

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perhaps undefined time, mass, and length mean you are a singularity. but then again, wouldn't you be one before you reach c?

$R=\frac{2Gm}{c^2}$

R is Schwarzchild radius, G is gravitational constant, m is mass, and c is speed of light

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American Heritage Dictionary

mass-energy equivalence: noun' date=' the physical principle that a measured quantity of energy is equivalent to a measured quantity of mass. The equivalence is expressed by Einsteins equation E=MC2.[/quote']

My advise to you is to look in a modern physics book not a dictionary, mass and energy are not equiavelnt as the enrgy of the object is depedent on that object's relative speed whereas the mass is not (and don't let anyone tell you otherwise as mass is defined to be the rest mass).

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perhaps undefined time' date=' mass, and length mean you are a singularity. but then again, wouldn't you be one before you reach c?

[math']R=\frac{2Gm}{c^2}[/math]

R is Schwarzchild radius, G is gravitational constant, m is mass, and c is speed of light

here is the formula for highest velocity without being a black hole:

$V^2=\frac{lc^4-4Gmc^2}{lc^2}$

I derived it from the previous formula, $m=\frac{m}{\sqrt{1-\frac{V^2}{c^2}}}$, and $l=l\sqrt{1-\frac{V^2}{c^2}}$

I set $\frac{1}{2}l\sqrt{1-\frac{V^2}{c^2}}=\frac{\frac{2Gm}{\sqrt{1-\frac{V^2}{c^2}}}{c^2}$

l is length, G is gravitational constant, m is mass, c is speed of light

if i messed up, feel free to tell me how to fix it

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It's interesting, but you did mess up as graviational collapse is not dependet on relative velocity (also you shouldn't really talk about mas schanging with relative velcotiy as in all but the most out-dated or most basic text mass is defined as rest mass which is a Lorentz scalar, infact generally we don't even talk about 'relativstic mass even as it merely represents the energy of the object).

Consider this: in relativty there invaraibly exists a frame of refrence where you are travelling at such a speed that according to your reasoning you would collapse into a black hole. However you are not a black hole so clearly any line of reasoning that says you are must be incorrect.

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so, if i were to travel at a certain velocity, to someone else, i would be a black hole, but to me i wouldn't?

does that mean that if someone survived the trip to the center of a black hole(ha), they may not know that they are in said black hole?

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so' date=' if i were to travel at a certain velocity, to someone else, i would be a black hole, but to me i wouldn't?

does that mean that if someone survived the trip to the center of a black hole(ha), they may not know that they are in said black hole?[/quote']

No it means the opposite i.e. an object doesn't become a black hole because it is whizzing past you at x miles per hour.

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My advise to you is to look in a modern physics book not a dictionary, mass and energy are not equiavelnt as the enrgy of the object is depedent on that object's relative speed whereas the mass is not (and don't let anyone tell you otherwise as mass is defined to be the rest mass).

What would be the universe's relative speed? I think our problem is that we are looking at different scales. On the atomic scale you are of course right about 'rest mass' and 'relative speeds', but on a cosmological scale I can still say such things as, "the sum of matter and energy is a constant", can't I?

aguy2

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Sort of. If you can move to the rest frame of the object then you can write E=mc2, telling you that the energy of the particle is proportional to its mass, but that is a pretty special case and one cannot always go to the rest from of a particle (eg a photon).

The correct equation is (for the 100th time):

$E^2=m^2c^4+p^2c^2$

where p is momentum. So you see if a particle is moving (ie p non-zero) then there is also energy coming from its motion and the energy of the particle is not entirely due to its mass.

You are probably correct in saying that a lot of the universe's energy is in mass, but by no means all. (I say 'probably' because we don't know what dark matter/dark energy is yet.)

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What would be the universe's relative speed? I think our problem is that we are looking at different scales. On the atomic scale you are of course right about 'rest mass' and 'relative speeds'' date=' but on a cosmological scale I can still say such things as, "the sum of matter and energy is a constant", can't I?

aguy2[/quote']

Well what dioyou mean by the universe's relative speed? For any relative speed you need to define what the speed is relative to! However there is a sort of 'refernce frame of the universe' (though don't read too much into that as it is merely the refernce frame where the universe is isotropic). But we still have a problem that energy can only truly be defined globally in flat spacetime, though if it is asymptotically flat we can have a good go at defining it, but there is no guarentee that the universe is asymptotically flat (though data from the CMBR certainly suggests the unievsre ay globally flat, but the problem is to prove the unievsre is flat you essientially need to measure a param,eter to 1000% accuracy).

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Well what dioyou mean by the universe's relative speed? For any relative speed you need to define what the speed is relative to! However there is a sort of 'refernce frame of the universe' (though don't read too much into that as it is merely the refernce frame where the universe is isotropic). But we still have a problem that energy can only truly be defined globally in flat spacetime, though if it is asymptotically flat we can have a good go at defining it, but there is no guarentee that the universe is asymptotically flat (though data from the CMBR certainly suggests the unievsre ay globally flat, but the problem is to prove the unievsre is flat you essientially need to measure a param,eter to 1000% accuracy).

In the current thread "Dark Energy" I presented a possible model of a non-isometric universe where the relative speed of the 'visible' universe might be determinable. Although I would value any constructive criticism of the model, for the purpose's of this thread I would like to restate the idea I presented in my original post concerning the possible cosmological equivance of time-space. If it reasonably possible that I can with a degree of validity say such things as, "the sum of matter and energy is a constant", might it be possible that the pattern displayed by matter-energy be extended to the other major constituent of reality, time-space? In other words can I say such things as "at the point of the Big Bang event, the amount of space available to the universe was at its minimum and the amount of time available to the universe was at its maximum?"

aguy2

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In the current thread "Dark Energy" I presented a possible model of a non-isometric universe where the relative speed of the 'visible' universe might be determinable.

You must make this clear: relative to what (you cannot talk about the relative speed of an object without syaing what the speed is relative to otherwise it tells us nothing).

Although I would value any constructive criticism of the model, for the purpose's of this thread I would like to restate the idea I presented in my original post concerning the possible cosmological equivance of time-space. If it reasonably possible that I can with a degree of validity say such things as, "the sum of matter and energy is a constant", might it be possible that the pattern displayed by matter-energy be extended to the other major constituent of reality, time-space? In other words can I say such things as "at the point of the Big Bang event, the amount of space available to the universe was at its minimum and the amount of time available to the universe was at its maximum?"

aguy2

The problem is that enrgy really isn't conserved in spacetime that is not asymptotically flat. Knowldge of Newtonian physics and the basic principles of general relativty is enoguh to see thta this must be the case as enrgy is not conserevd in non-inertial refernce frames in Newtonian physics, yet in general relativty inertial and non-inertial refrence frames are given an equality of sorts.

ou msut also be clear what you mean by maximum aviadable space and maximum avidable time as thta to me has no obvious meaning.

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You must make clear: relative to what (you cannot talk about the relative speed of an object without sying what the speed is relative to otherwise it tells us nothing).

Relative to the anti-matter co-universe as proposed in post #51 of the 'Dark Energy' thread.

Ou msut also be clear what you mean by maximum aviadable space and maximum avidable time as thta to me has no obvious meaning.

The model presented in post#51 of the 'Dark Energy' thread proposes a model of finite, closed, and possibly osscilating co-universes. Under these conditions time-space would have minimum and maximum values.

aguy2

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