e=mc2 = wrong? Photon mass = 0 yet has energy? Need help Please.

Ok. So i was thinking last night trying to get to sleep and physics burst into my brain which kept me up for an extra 2 hours.

So...

e=mc2 (that two is a squared)

So wikipedia tells us that a photon has no mass.
Photon mass = 0
so e = 0 x speed of light squared
so e = 0?

But it also says that a photon has "For visible light the energy carried by a single photon is around 4×10–19 joules"
energy of photon = 4×10–19 joules
e=mc2
4×10–19 joules = 0 x speed of light squared.
4×10–19 joules = 0?

I dont get it.

Now also apparently the faster something the more mass it has.

I am thinking logically that this is incorrect.

If i were to shoot a bullet and it was sped up to the speed of light I still believe that bullet would weigh the same. I bet if i were to get a scales and travel at the same time as this bullet which is traveling sideway but yet going in a downward direction on 9.8 meters a second due to earths gravity, and i were to put the scales below it which its travelling this fast, it's downward force would be the same and its mass would not have changed.

However i believe that it would take a lot of energy to stop that bullet from traveling and would take the same amount of energy to get it back to that speed again. How can the bullet gain mass when it simply doesn't change size and no further electrons, protons, any other particles have joined up with it to give it weight?

Now dont be teling me by trying to transfigure that e = mc2 equation around to show the mass of the bullet = this amount because its energy levels are so high due to it being at such a huge speed. It took a lot of energy to get that bullet moving and it will take a lot of energy to stop that bullet moving. It just doesn't make sense that it has gained any mass.

Also on this matter. The speed of light can change! It's been proven in experiments and apparently it used to be slower when the universe was smaller.... It's also been slowed down by experiments.

How is it this equation of e = mc2 is right? I just dont see it.



Please someone help me!?!??!

E_0 = m_0 c² refers to the restenergy if you plug in the restmass m_0 and in this context would mean that you can not bring a photon to rest since it has no restmass

but:
E= m c² for the relaticistic mass m which even a photon has

the best way to look at is the total energy of a particle
E = sqrt ( (m_0)² c^4 + p²c²)
since m_0 = 0 for a photon its energy is totally momentum like:
E = pc
so your photon has relativistic energy, relativistic mass (due to its momentum: m_r = E/c² = p/c)

you can also reread this here in a maybe even more conveniant form

[edit on 9-4-2008 by puerk]

The question your post also asks is, does mass really exist or is it an illusion of speed?

Maybe this is why the holographic principle keeps showing up in equations.

At the end of the day the only thing that exists is light. The Bible also says that God is Light. An interesting book to read is God at the Speed of Light.

Maybe all that exists is pure light that gets disturbed by quantum fluctuations which in turn produces an infinite number of universes.

Maybe light escapes into a vacuum and takes on a speed. From our point of view we call it the speed of light but actually no such thing exists beyond our perception.

Things that make you go hmmmm.....

This is the message we have heard from him and proclaim to you, that God is light and in him is no darkness at all. [1 Jn 1:5 RSV]

Good Post.

[edit on 9-4-2008 by polomontana]

[edit on 9-4-2008 by polomontana]

reply to post by polomontana


That's stretching it a great deal.

God has nothing to do with this.

Originally posted by dave420
reply to post by polomontana

 

That's stretching it a great deal.

God has nothing to do with this.

That's stretching it how? You have to use words to communicate the point that your trying to get across. Just saying it's stretching it is a bit abstract.

I think in 2008 we have to become freethinkers instead of close-minded believers, wether that belief be secular or religious in nature.

We have to expand beyond our perception if we are ever going to understand the nature of reality.

God could be the sum of all things. The sum of every energy state throughout the multiverse or the wave function of the multiverse.

This is not far fetched or a stretch unless it runs up against a belief system. Some think any mention of God threatens what they already believe therefore they rather remain in the cave instead of coming out in the open and experiencing the light of day.

[edit on 9-4-2008 by polomontana]

Originally posted by polomontana
We have to expand beyond our perception if we are ever going to understand the nature of reality.

God could be the sum of all things. The sum of every energy state throughout the multiverse or the wave function of the multiverse.

This is not far fetched or a stretch unless it runs up against a belief system. Some think any mention of God threatens what they already believe therefore they rather remain in the cave instead of coming out in the open and experiencing the light of day.

the problem is (which i also would like to call "stretching") you mix scientific terms to senseless constructs.. if you want to go beyond your perception but still want to communicate your thoughts it is totally senseless to use a language unknown/meaningless to most others

an other problem i see is that you talk about science (or try to do so) but dont apply critical rationalism (in the popper sense).. setting up claims about the nature of god using terms of science but producing an meaningless, isolated construct, with no chance of falsification and no explainatory value beyond its very statement, is just useless for discussion since it is closed and undiscussable

At the end of the day the only thing that exists is light.

whats about gravity, space itself and vacuum fluctuations?

Maybe all that exists is pure light that gets disturbed by quantum fluctuations which in turn produces an infinite number of universes.
/quote]
this is one of those meaningless statements.. either explain it consistent with science terms or dont use them since its irritating and wrong

Maybe light escapes into a vacuum and takes on a speed. From our point of view we call it the speed of light but actually no such thing exists beyond our perception.

from where?
"a vacuum" means there are other vacui?
where does your "actually" come from?


it just reads like "bluff-word + bluff-word = god + bigger bluff-word"

Originally posted by DaRAGE
Please someone help me!?!??!

I'll try to clear it up for you.

You may have heard about experiments with plasmas or Bose Einstein condensates that have "slowed" down light, but really they are only confining to to a small space where it is still moving at the speed of light, but just kind of trapped. Photons all have an inherent speed of light, and travel at that speed in a vacuum, but propagate through other material - like plastic, glass, water, air - at different speeds depending on their frequency (energy) and are bent, but the individual quanta of light is still zooming around at light speed, it just has to cover more distance because of refraction and absorbtion/re-emmition, and collisions when traveling through different media.

There have been a number of experiments that have proven that E=mc^2, such as passing high velocity particles through magnetic fields and measuring their mass, or crashing particles into one another in super fast particle accelerators, so your impossible bullet experiment is not necessary.

In very simple terms, this "mass" and "energy" you speak of is the same thing, and are merely subjective semantics leftover from classical physics (Newton). It also gave rise to Quantum physics [i.e. wave-particle duality] which has also been proven by observation. Your bullet is made up of energy that you see as matter particles which have the same properties of the kinetic energy that you introduced into it, and the inertia acting on it. This basically means that both "mass" and "energy" (same thing) promote curved space time - that is, they both cause gravity. Photons do not have a mass in the Newtonian sense, but they do have momentum and therefore energy - which bends space time and can be affected by gravity. Gravity is a mutually attracting force, and recent observations have shown the light is in fact affected by gravity. As it would take infinite amount of energy to propel something with a nonzero rest mass (without an upper bound, never with a nonzero lower bound, all all calulations are constantly getting smaller and smaller as accuracy increases) to the speed of light, photons cannot have mass under the current model. You could say, "Well, what if there was a particle that DID travel faster than light?" and people HAVE. One is called a tachyon; however, it has never been observed in reality besides the reality of science fiction.

To make it simple again, mass can be thought of as condensed energy to give a crude ad hoc model: You know how saturated water vapor in the air codenses into water droplets under certain conditions? Well, you might say that saturated energy in space time condenses into matter under contain conditions. We could say that "clouds" [visible mass] increases as "saturation condenses" [invisible energy] increases. You might compare this to dark matter, which is proposed to have local gravitational effects, and dark energy, which is evenly distributed throughout the universe and has a universal gravitational effect.

The LHC set to go online soon has a good chance of letting us know exactly what causes mass and energy "massergy " to curve spacetime, and why some particles have mass while others don't, because it can work in the energy frequencies where the Higgs Boson – something theorized to be responsible for giving particles mass - is bound to exist, if it indeed does.

Does this clear things up?

As ive stated in other threads i think trying to travel at or over the speed of light impossible with our current thinking. What i do believe is that light is the energy we need to encompass to travel at that speed and possibly exceed it.

Using the light as a propulsion method is i believe the only way to surpass the the e=mc2 when using conventional propulsion methods

Good question!

The bullet you mentioned would weigh the same as it did before in your thought experiment, because if you were traveling at the same speed as the bullet, it would be moving at a velocity of 0 with respect to you.

The difference in mass (correctly stated by puerk) is a change in the relativistic mass. That relativistic mass only exists as an observation by an observer who is not moving with the bullet.

Now, the part that really gets fun is when you consider that the speed of light is variable, under certain conditions such as in a younger universe. I suggest you think about waves in a puddle of water. That's not all I can say on the subject, but it is all I will say at this time.

TheRedneck

puerk,

Your whole post is basically saying, you can only talk about science if it fits my worldview.

This is silly and any scientist worth his/her salt will tell you that science is a very, very incomplete picture of reality.

Science is not immune to metaphysics, paranormal or ufology. Science is only limited by your perception of reality. If you are a secularist or athiest you want the world to be wrapped in a box that fits your pre-existing belief system. So when people incorporate science into these things your reason shuts off and your belief kicks in.

I'm glad Dr. Michio said on Coast2Coast AM that physics was catching up with metaphysics.

Metaphysics, paranormal events and ufology all are "natural explanations" When a person says they are looking for a natural explanation it just means they are looking for an explanation that supports what they already believe.

Paranormal and ufology would be natural explanations that we don't fully understand yet. Just like if you were to go back 2,000 years ago and clone a sheep, the people of that time would see it as a supernatural event.

So your saying you can only see science in the way that you see it. Sorry that makes no sense. Any mention of God and some people lose all reason.

Have you ever heard of M-Theory? You asked where would the vacuum originate. It would originate in the bulk.

An infinite number of quantum fluctuations occur in the bulk which in turn cause a vacuum to occur. Some produce universes with life and some produce dead universes. Light takes on a speed when it enters the vacuum. To the observer within the universe it's seen as the speed of light and many observers will see their reality as all that there is. Light is actually infinite and has no speed. This goes back to Plato and the allegory of the cave. You can't see past your perception because ignorance is bliss. There's comfort in the cave.

Dispute what I'm saying through logic and reason. The statement your not using science in the right way is silly on it's face. Don't lash out with nonsense, dispute and debate with reason and logic.

Originally posted by polomontana
Your whole post is basically saying, you can only talk about science if it fits my worldview.

since there is a large field called philosophy of science, there are also well defined boundaries what is science and what is not.. so if you want you can look this critical rationalism and for addition okhams razor up

if you have an other picture of science, i have no problem with it but then please use other terminology to dont get things mixed up

Science is not immune to metaphysics, paranormal or ufology. Science is only limited by your perception of reality.

no, science is limited by its methods "hypothesis (incorporating the known theorys on this subject) + theory = explaination + falsificable predicitions" as long as the predictions hold its favourized and if the are not satisfied, the theory is abandoned

If you are a secularist or athiest you want the world to be wrapped in a box that fits your pre-existing belief system. So when people incorporate science into these things your reason shuts off and your belief kicks in.

i would be pleased if you would stop explaining my own character to me since you dont know me and my background
i consider the question "is god existent" one that can not be answered (neither yes nor no) by science since it fails falsificability.. so i would never think about incorporating gods existence or notexistence in my picture of the world.. i just ignore the matter as unanswerable

Metaphysics, paranormal events and ufology all are "natural explanations" When a person says they are looking for a natural explanation it just means they are looking for an explanation that supports what they already believe.

yes, since all working theories have to be (via correspondence principle) special cases of a more general law under some conditions (as newtons gravity theory is the classical limit of general relativity or as classical mechanics is the highenergy and large space limit for quantum mechanics)

this is only the way philosophy and most scientists (including me) look at science.. you are of course free to build up your own science but then please just dont say such things as quantum fluctuations of light produces multiverses, which could be mistakenly understood as terms from physics

Have you ever heard of M-Theory? You asked where would the vacuum originate. It would originate in the bulk.

have heard of m theory and in maybe 1-2 years i will understand it..
for now i work on semiclassical quantum gravity (putting the expectation value of the energy momentum tensor of a quantum field as additional component of the energy momentum tensor, but not considering space quantizised itself)

Light is actually infinite and has no speed. This goes back to Plato and the allegory of the cave. You can't see past your perception because ignorance is bliss. There's comfort in the cave.

and you are sure that it is worth throwing all good working experimental confirmed theorys away for a saying without any explainatory value?

a "better" theory of light has to fullfill the following properties:
predict observed mechanisms of creation (radiating charges, laser, matter-antimatter annihilation), absorption (heat, affect chemical bondings, fission of nuclei via gamma rays etc) and interaction with matter/energy (frequency dependend damping in media, pair production, radiation pressure, bendig due to gravity etc)

your so far stated does none, so i will wait until i can tell what it is worth



[edit on 10-4-2008 by puerk]

Don't bosons have energy although they have no mass? Bosons have photons in their family a laser is composed of photons ....lasers do damage. so hows that work if light has no energy?


Even crazier All fermions-particles with mass are really bosons temporarily manifesting themselves as fermions. you know a harmonic of the background radiation. wave theory string theory. solid particles with mass are really just a harmonic of the universal background energy signature. when the energy wave stacks up and creates a harmonic it manifests its self as a fermion. a packet of energy(boson) with enough juice to appear solid and thus a fermion. they then can transition back into a boson from a solid mass state. the transition is a meson particle.

although I do admit that einstein is getting refuted more and more these days. but for lots of reasons other than light has no mass and therefor no energy, but just because something has no mass by no means means it has no energy. try telling that to a destructive laser beam.

[edit on 10-4-2008 by BASSPLYR]

[edit on 10-4-2008 by BASSPLYR]

Originally posted by BASSPLYR
Don't bosons have energy although they have no mass? Bosons have photons in their family a laser is composed of photons ....lasers do damage. so hows that work if light has no energy?

some bosons have rest mass and thereby rest energy for example W and Z bosons, others dont have rest mass and rest energy photons for instance
but they all have total energy which is the sum of kinetic and rest energy

Even crazier All fermions-particles with mass are really bosons temporarily manifesting themselves as fermions.

can you state where this comes from?

you know a harmonic of the background radiation. wave theory string theory. solid particles with mass are really just a harmonic of the universal background energy signature. when the energy wave stacks up and creates a harmonic it manifests its self as a fermion. a packet of energy(boson) with enough juice to appear solid and thus a fermion. they then can transition back into a boson from a solid mass state. the transition is a meson particle.

sounds pretty bogus and also some ref would be nice
bosons are just particles with integer spin and fermions are such with halfinteger spin... in both families are massive particles but the perception of "solidity" in some sense of incompressability is due to the pauli principle on fermions because their half integer spin imposes a antisymmetric wavefunction (which would get zero for 2 particles in the same state)

what does the word transition mean for you in this context? there are many different mesons and they all only build up from quarks so they have much more energy than usual fermions so where is your energy conservation.. or please get just some examples to talk about

although I do admit that einstein is getting refuted more and more these days. but for lots of reasons other than light has no mass and therefor no energy, but just because something has no mass by no means means it has no energy. try telling that to a destructive laser beam.

please differentiate between rest mass and rest energy on the one side and total energy (containing its kinetic energy (depending on observer) and its restenergy) on the other

reply to post by BASSPLYR

I do admit that einstein is getting refuted more and more these days. but for lots of reasons other than light has no mass and therefor no energy, but just because something has no mass by no means means it has no energy. try telling that to a destructive laser beam.

Einstein is not being refuted; it simply appears so. Modern science is doing what my father used to call "going around the block to get next door". And there have been a few detours into dead-end alleys. But it'll eventually get there.

TheRedneck

I thought e=mc2 tries to explain mass & energy at a super "sub-atomic" level. I'm thinking... something that has no mass will not be influenced by gravity. Thus the difference at this level.


Don't need to use this stuff with my work... I liked the OP's subject and thought. I could be wrong about mine.

something that has no mass will not be influenced by gravity

everything that exists in our space time will affect and be affected by gravity.. since every existing object (field, particle, space time structure, space itself etc) has an nonzero energy and therefore applies as contributor to the energy momentum tensor in GR

All matter/mass in motion contains energy. Even lead, (very heavy) is still in motion. The rotation of earth, the solar system and our Galaxy maintains that motion.

As I've said before, being concerned about inventing propulsions systems that can travel at near or in excess of the speed of light is a waste of time.

Why?

Consider the purpose, i.e. space travel. If you look at the distance between star systems it becomes rapidly apparent that moving at (only) the speed of light is MUCH TOO SLOW.

If we travel to other star systems, it will not be with propulsion systems. It will only be feasible using some kind of dimensional travel, or 'turning the corner' into the 4th or 5th dimension. A common example is through use of 'wormholes' formed by the creation of black holes that connect through space time.

However, this is just one paradigm. Of course, since we are three-dimensional beings it may be impossible to accomplish this; it remains to be seen.

My main point, though, is that it is useless to plan for using near-FTL propulsion for space travel.

Another problem with use of such dimensional travel such as wormholes, is that conventional theory shows it is dangerous to have any such star gates too near a planet or even a solar system. So we stilll have to overcome siginifcant limitations to get to that point.

2 cents.

Matter which moves at the speed of light becomes energy

m = the mass you would have if the energy was converted to mass(comes to rest) = E/c^2
c^2 = 8.99 X 10^16 (m/s)^2
E = energy of the photon, which could be anything along a spectrum, from your example E = 4 x 10^-19 kg (m/s)^2

so the mass of this photon would be 4.45 x 10^-36 kg if it came to rest

The energy of the bullet can be determined according to its mass at rest, just multiply it by c^2

Wow thanks for the posts. I'm pretty clear on it all now except im a bit confused with this part:

If experiments have been made using electro-magnets to measure magnetic fields, etc, of just say a high speed passing bullet to determine that it has more mass when going faster. But if i was going at the same speed at that bullet and measured its magnetic field, it wouldn't say its got more mass at all. It's only relative to how fast it's going compared to me?

Is that right? If it's right i dont know how to get my head around it except to say m = e/c2 ;-P or is that m = c2/e ? ;-P

Anywyas thanks for you help ;-P (especially Former CIA Agent). (Definately not puerk) ;-P