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Thanks -_-!

- Thread starter cobrastrike
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Thanks -_-!

- #2

DaveC426913

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Nothing with mass can accelerate to the speed of light. The closer you get to it, the more energy it will take to get closer. It is an asymptotic limit.

Thanks -_-!

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Hence, anything without mass can be faster than light: velocity of phase/group of EM waves, gamma-ray burst, neutrinos, and also initial acceleration of light (m/s² → v/t ), light’s initial acceleration shouldn’t exceed an acceleration of c (v/t), but it exceeds because it has no mass.Nothing with mass can accelerate to the speed of light. The closer you get to it, the more energy it will take to get closer. It is an asymptotic limit.

Extending this thought, if something has no mass then it can be faster than light, hence I thought it is logic the theory, that is said already observed in practice, that static fields (magnetic and electric) are at least 20 billion times faster than light.

As well, http://www.youtube.com/watch?v=Z8Hwqg9_oA8", which can be mathematically verified (f≥c/L)

As far as I could understand, "Nothing can be faster than light", except if it has no mass or negative mass.

My question is, could phase-shifted oscillations produce a kind of negative mass effect?

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- #4

K^2

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No. Anything with no mass travels AT the speed of light. E.g. light.

- #5

DaveC426913

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No, this does not follow.Hence, anything without mass can be faster than light: velocity of phase/group of EM waves, gamma-ray burst, neutrinos,

Light does not accelerate. It is emitted at c.and also initial acceleration of light (m/s² → v/t ), light’s initial acceleration shouldn’t exceed an acceleration of c (v/t), but it exceeds because it has no mass.

It can't.Extending this thought, if something has no mass then it can be faster than light,

No. Fields are pervasive - as in: theyhence I thought it is logic the theory, that is said already observed in practice, that static fields (magnetic and electric) are at least 20 billion times faster than light.

CertainAs well, http://www.youtube.com/watch?v=Z8Hwqg9_oA8", which can be mathematically verified (f≥c/L)

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Yes, it is. Space does it all the time.

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Acceleration is the rate of change of velocity over time (∆v/∆t), hence, how could the light be emitted, with instantaneous speed up to c, without initial acceleration?Light does not accelerate. It is emitted at c.

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f95toli

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(a more scientific answer is that a photon is just an

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From what I have understood, then, is there a kind of “slot” that always travels at c, independently whether it is occupied by a photon or not?

(a more scientific answer is that a photon is just anexcitationof a tempora-spatial mode, i.e. that mode -which "travels" at c- either is or isn't occupied)

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p.s. im only 15

- #12

russ_watters

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T=0 therefore v/t= undefinedAcceleration is the rate of change of velocity over time (∆v/∆t), hence, how could the light be emitted, with instantaneous speed up to c, without initial acceleration?

- #13

Danger

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Check out Cherenkov radiation as an example.

Resident scientists, I have quite a record for using incorrect terminology when trying to express myself, so please feel free to correct such.

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- #15

DaveC426913

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Nope. Light does not accelerate when subjected to gravity; it simply curves along the geodesic.

A massive object can be placed stationary with respect to a gravitational object such as Earth or a BH. From that point, it will begin to accelerate, due to the curvature of space toward the object. But you cannot place a beam of light stationary wrt a gravitational object, thus it does not accelerate toward it.

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DaveC426913

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"Space" doesn't "do" anything, including "go" anywhere. ThingsYes, it is. Space does it all the time.

Even when the universe is expanding, there is no "fabric" that is moving. It is simply that objects far apart are getting farther apart.

- #17

DaveC426913

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No. Not sure where this slot came from.From what I have understood, then, is there a kind of “slot” that always travels at c, independently whether it is occupied by a photon or not?

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I think it is not undefined; it is infinity.T=0 therefore v/t= undefined

v/t ⇒ S/t²

lim (1/t²) = +∞

t→0

http://en.wikipedia.org/wiki/List_of_limits#Simple_functions

- #19

DaveC426913

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Regardless, the photon moves at c and only c. Photons do not experience time.I think it is not undefined; it is infinity.

v/t ⇒ S/t²

lim (1/t²) = +∞

t→0

http://en.wikipedia.org/wiki/List_of_limits#Simple_functions

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However, observers experience time. Would an observer see an emitted photon as it had acquired instantaneous velocity c in a time close to zero, observing infinity acceleration?Regardless, the photon moves at c and only c. Photons do not experience time.

- #21

DaveC426913

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Yes (if an observer could "see" a photon emitted, which is challenging).However, observers experience time. Would an observer see an emitted photon as it had acquired instantaneous velocity c in a time close to zero, observing infinity acceleration?

- #22

K^2

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In quantum electrodynamics, yes. The state of a traveling photon always exists. When you "create" a photon, you merely excite that state. That's called the second quantization of electromagnetic field. So in a way, looking at it as something that always travels at c and you simply flip it on and off is consistent with our understanding of electromagnetic wave.From what I have understood, then, is there a kind of “slot” that always travels at c, independently whether it is occupied by a photon or not?

Just keep in mind that you're getting very close to the slippery edge of a rabbit hole that is quantum gravity.

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hmmmm, that's interesting. So if light is slowed down as it passes through a medium, does this mean that it isn't accelerating although there's aLight does not accelerate. It is emitted at c.

.

If light can't accelerate, then forces cannot act on light, is that true? The definition of a force (as I know it) is something that causes an acceleration...

- #25

Danger

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As I mentioned earlier, the individual photons still travel athmmmm, that's interesting. So if light is slowed down as it passes through a medium, does this mean that it isn't accelerating although there's achange in velocity? That's rather strange to me...

If light can't accelerate, then forces cannot act on light, is that true? The definition of a force (as I know it) is something that causes an acceleration...

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