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Time can't exist without matter (mass) and motion

by Lakshya
Tags: exist, mass, matter, motion, time
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Chris Hillman
#19
Nov16-07, 12:36 AM
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Right, a massless particle can't be at rest, so it cannot have and does not have a "rest mass", but it can and does have energy and momentum.
Lakshya
#20
Nov16-07, 01:51 AM
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Quote Quote by Chris Hillman View Post
Right, a massless particle can't be at rest, so it cannot have and does not have a "rest mass", but it can and does have energy and momentum.
But the E and p at rest are 0.
Garth
#21
Nov16-07, 02:32 AM
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Quote Quote by Lakshya View Post
But the E and p at rest are 0.
Chris meant to add "when it is moving at c". I think that was taken as read.

i.e. 'a massless particle can't be at rest, so it cannot have and does not have a "rest mass", but it can and does have energy and momentum when it is moving at c'.

Garth
nicky nichols
#22
Nov17-07, 04:55 PM
P: 26
instead to say does time cease to exist if it cannot be measured or observed because surely all clocks require to be made of mass and energy
Lakshya
#23
Nov21-07, 08:25 AM
P: 72
Quote Quote by nicky nichols View Post
instead to say does time cease to exist if it cannot be measured or observed because surely all clocks require to be made of mass and energy
Nice argument nicky. I am looking 4ward to carry a research on it.
Lakshya
#24
Nov23-07, 06:52 AM
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Is it going to rest in peace? Is there nobody out there to reply?
Garth
#25
Nov23-07, 07:28 AM
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Quote Quote by Lakshya View Post
Is it going to rest in peace? Is there nobody out there to reply?
We have answered your post, have you taken in and understood what we have said?

You may appreciate the quote from the fourth century:

What then is time? I know well enough what it is, provided that nobody asks me; but if I am asked what it is and try to explain, I am baffled.
St. Augustine of Hippo (He was a bishop in N.Africa). Confessions XI 14 (AD 354-430)

In that same chapter he also said , as a prayer to God, amongst other sayings:
It is therefore true to say that when you had not made anything, there was not time, because time itself was of your making.
( i.e. time 'began' when the universe did - not bad for the fourth century!)
and
How can the past and future be when the past no longer is and the future is not yet? As for the present, if it were always present and never moved on to become the past, it would not be time but eternity.

You may find the discussion of this old thread useful to read: The Nature of Time?.

What other questions do you want to ask?
We will do our best to answer them.

Garth
hejin
#26
Nov23-07, 03:53 PM
P: 8
Quote Quote by Lakshya View Post
Is it going to rest in peace? Is there nobody out there to reply?
This is a basic question so basic that the basic interpretation of GR would have to be changed and those theories like BB would fail.

The existence of time is the sole requirement of the assumption that spacetime is really a curved matter. Gauss studied curved surface, very realistic. Based on Gauss forms of curved surface, Riemann proposed curved `surface` of whatever dimension. These are math!!

GR, a physical theory, considers the math to be reality. So the universe based on BB (big bang) must be the curved entity in the meaning of Gauss but 4-dimensional. This is the standard interpretation of GR.

Another interpretation is based on real matter and is consistent to Quantum Mechanics: Physical measurements give an impression of curved spacetime. Based on this interpretion, cosmic redshift is Doppler redshift. The physical universe is infinite but physical constants may change and the corresponding physical measurements give an impression of `Big Bang`. And time does not exist as you suggest!

Please do not ban me!!

Jin He
Pippo
#27
Dec3-07, 05:45 PM
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According to me "no mass and not motion" , so no observers as well, means nothing, so why the time should exist?
Lakshya
#28
Dec4-07, 07:46 AM
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And y do u think so? I think the answer is c.
Pippo
#29
Dec4-07, 02:55 PM
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Quote Quote by Lakshya View Post
And y do u think so? I think the answer is c.
I could fully agree about C, but we are supposing no observers, no masses, so where C is originated from ?
Lakshya
#30
Dec11-07, 07:07 AM
P: 72
Quote Quote by Pippo View Post
I could fully agree about C, but we are supposing no observers, no masses, so where C is originated from ?
Bcoz light takes some time to reach our eyes and we can never be sure if anything exists at present. We can be sure of past. Sorr I am writing it too shortly.
Pippo
#31
Dec11-07, 02:50 PM
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Quote Quote by Lakshya View Post
Bcoz light takes some time to reach our eyes and we can never be sure if anything exists at present. We can be sure of past. Sorr I am writing it too shortly.
Yes but even the light travel through the space, so the question is : can the light reach
a "no place" ? (no space, no time , no everything)
Lakshya
#32
Dec12-07, 08:22 AM
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Quote Quote by Pippo View Post
Yes but even the light travel through the space, so the question is : can the light reach
a "no place" ? (no space, no time , no everything)
The answer is holes (black, white and worm).
EssentialNature
#33
Dec12-07, 10:40 PM
P: 2
I believe the line of reasoning that a photon has zero rest mass is this:

According to Special Relativity as an object with mass approaches the speed of light its mass increases. The limit equation is that as an object with mass approaches the speed of light its mass approaches infinity. So if an object is moving at the speed of light it cannot have any rest mass.

One must understand the purpose of an equation and from what I have seen many explanations are not very good at getting into explaining the full essence of such equations. That is because typically a large amount of background is assumed. There are non-mathematical books that explain physics, like Brian Green books. These are good for gaining some insights into physics. There are textbooks with strong mathematical books. These usually assume you took all the prerequisites, i.e. they assume a strong background. There are technical papers that almost always assume a strong background. There are articles like those in wiki that run the gambit. The in between books and especially articles which show the math and do a detailed explanation of each term with simple explanations are more harder to find.

Let me explain the equation . This is a composite equation. The energy contained in “rest mass of matter” is the value m2c4. The motional energy and photonic energy is the p2c2. The following web page has some good information about energy.
http://en.wikipedia.org/wiki/Energy
An except from this is:
2. On the other hand, in the key equation m2c4 = E2 − p2c2, the contribution mc2 is called the rest energy, and all other contributions to the energy are called kinetic energy. For a particle that has mass, this implies that the kinetic energy is 0.5p2 / m at speeds much smaller than c, as can be proved by writing E = mc2 √(1 + p2m − 2c − 2) and expanding the square root to lowest order. By this line of reasoning, the energy of a photon is entirely kinetic, because the photon is massless and has no rest energy. This expression is useful, for example, when the energy-versus-momentum relationship is of primary interest.
Technically speaking, this paragraph does not explain why a photon has zero rest mass. It simply states it. So I do not like the wording in this document about why the photon rest mass is zero.

Always remember there is a big difference between photons and particles. When you look at equations you must ask two questions: does this apply to particles, if so then how; does this apply to photons, if so then how. You will likely get different perspectives depending on whether it is a particle or a photon. One other thing to note is to always be careful about rest mass energy verses relativistic energy of a particle due to motion.

Let me explain my point by discussing the wave equation. http://en.wikipedia.org/wiki/De_Broglie_hypothesis
http://en.wikipedia.org/wiki/Wave-particle_duality

When one uses the wave equation especially for matter realize that it deals with the interaction of objects. The is explained as follows:
From http://en.wikipedia.org/wiki/De_Broglie_hypothesis
“the greater the energy, the larger the frequency and the shorter (smaller) the wavelength”

So now ask yourself, what energy are they talking about?
Another question, are we talking about particles or photons?
By the earlier principle, differentiate particles and photons.
It does apply to both. So let me simply discuss the application to particles.
Is the energy dealing with the rest mass, motion, or both?
When you split apart the statement into more detailed questions like this you begin to better understand the nature of the statement and the equations.

This energy is the energy of motion not in rest mass because the equation uses the mass and velocity of a particle. Higher velocity is higher energy is a shorter wavelength.

Principle: motion has no meaning for a single isolated particle. It must be with respect to two or more. A simple statement but remembering it can help clarify.

The energy of motion is in relative velocity. Something moving toward you, which increases its velocity, will increase its energy with respect to you. This will increase this frequency factor. However, you can also increase the energy by accelerating towards this object. If you accelerate towards the object you increase the relative velocity. This increases the relative motional energy and increases this frequency factor also. Your increase in speed effect your view of this objects “frequency”. This frequency factor is what is used on calculating how any interactions between you and this other object will happen.

It is an equation used to help compute outcomes for interactions.

So I hope this helps. I tried to add some principles for understanding what you are reading on physics and how to explore thoughts on physics.

If you might guess these days I do like wiki articles on Physics. They are a nice resource for reference and look up.
Pippo
#34
Dec26-07, 05:07 PM
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Quote Quote by Lakshya View Post
The answer is holes (black, white and worm).
My question is : if holes are something can they be compared with a "no place" (a nothing) ?
Lakshya
#35
Dec27-07, 07:05 AM
P: 72
Quote Quote by Pippo View Post
My question is : if holes are something can they be compared with a "no place" (a nothing) ?
Yes, bcoz there mechanism is undetectable. BHs tend to go for a singularity or nospace. WHs appearr from a singularity or noplace. And WoHs are a tunnel between BHs and WHs or they travel between no places.
Himanshu
#36
Dec27-07, 12:49 PM
P: 67
Quote Quote by Lakshya View Post
Yes, bcoz there mechanism is undetectable. BHs tend to go for a singularity or nospace. WHs appearr from a singularity or noplace. And WoHs are a tunnel between BHs and WHs or they travel between no places.
I wont call Black Holes as 'no place'. Its really a place that we don't understand at all. Its a region of space that we cannot describe completely. And today to describe a Black Hole completely has become the holy grail of modern physics (that's an indirect way of talking about 'unification').

To EssentialNature.

That was a great article!
I have always been curious to know where did E=M_0C2 came from. I know the derivation of E=MC2 but it uses on its way M_0C2 as a term that represents the rest mass energy of an object. How do we know this? Is there a concrete derivation of this or did this come to Einstein as a dream?


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