dhd - before u graduate from high school, you will learn about young's double slit. this experiment describes how light cannot be separated into particles or waves alone.

He said he drinks wine. I don't think he's a student.

Not to mention that he does have a point. Single electrons used in a double slit experiment can be toned down to only have a single electron pass at one time, giving clear single point collisions with the detector. The overall pattern still remains an interference pattern. One test that shows that a particle can have wave behaviour.

Still, it's hard to say that a photon is:
A) a particle only
B) a wave only
C) both a particle and a wave until a measurement is made
D) none of the above

ok i give up, electrons? what? you guys can continue this thread. im done.

and to answer the original question: photons have no mass, but they have momentum.

It can! Close one of the slits and it (light) behaves like .... (you could argue that this is not a double-slit-situation)
Open both slits and it behaves like .... (but this IS a double-slit-situation)

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If everyone had even a basic grasp of scientific principles, this planet would be a better place (Phil Plait)

Die Lücke, die wir hinterlassen, ersetzt uns vollkommen (Carl Heinz Schroth)

Why? Have you thought of/heard about fullerenes´ behaviour in a double-slit experiment? The outcome is the same as with photons, electrons, etc

100% agreement !

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If everyone had even a basic grasp of scientific principles, this planet would be a better place (Phil Plait)

Die Lücke, die wir hinterlassen, ersetzt uns vollkommen (Carl Heinz Schroth)

Yes, I think that´s more or less what I wanted to say in my posts

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If everyone had even a basic grasp of scientific principles, this planet would be a better place (Phil Plait)

Die Lücke, die wir hinterlassen, ersetzt uns vollkommen (Carl Heinz Schroth)

Agreed!

After a while I decided to comment again on your post which referred to my statement:
what´s the meaning of "rest mass"? What´s the meaning of "relativistic mass"? There´s no rest mass, and no relativistic mass, there´s only mass, invariant, independent of the frame of reference

Very seriously: All textbooks talking about rest mass and relativistic mass should be rewritten. This may sound arrogant, but I´m sure there are some experts here on this forum who can explain it much better than I can do.

From my point of view: Do you really believe that the mass of protons, neutons, electrons, etc increases by acceleration? Where does the addititional mass come from? Where does this additional mass go to when a "massive" body decelerates?
If you talk about "rest mass": in "rest relative to what"? We (you) move at approx. 30 km/s around the Sun, the Sun moves approx. at 200 km/s around our galaxy´s centre, our galaxy moves .... toward the Great Attractor

I would be happy to be corrected by BAUT´s experts

__________________
If everyone had even a basic grasp of scientific principles, this planet would be a better place (Phil Plait)

Die Lücke, die wir hinterlassen, ersetzt uns vollkommen (Carl Heinz Schroth)

Two weird links:
http://en.wikipedia.org/wiki/Spaghettification
(apart from name, "spaghettification", it's weird the "tidal behaviour" due to gravity effects, which gets water REPELLED; I must examine the explanation for this)

Pulling gravity:
http://bioch.szote.u-szeged.hu/astrojan/gravity.htm

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-- Jumpjack --

why dont u prove the equations wrong instead of writing this. the worst kind of forum poster, is someone who pretends to know what they are talking about, by reading on the subject on wikipedia.

mrel=m/sqrt(1-(v/c)^2)

By definition, isn't rest mass a constant?

Therefore, we have our rest mass, and everything else is a lorentz transform. Once you involve the transform, you end up with relativistic mass(or inertial mass) which is relative. It's a necessity for the laws of physics to be uniform regardless of position.

The textbooks are fine.

Which equations?

I´m actually not a perfect wikipedia-fan

__________________
If everyone had even a basic grasp of scientific principles, this planet would be a better place (Phil Plait)

Die Lücke, die wir hinterlassen, ersetzt uns vollkommen (Carl Heinz Schroth)

Where did you find this?

__________________
If everyone had even a basic grasp of scientific principles, this planet would be a better place (Phil Plait)

Die Lücke, die wir hinterlassen, ersetzt uns vollkommen (Carl Heinz Schroth)

I think so

? position ?

__________________
If everyone had even a basic grasp of scientific principles, this planet would be a better place (Phil Plait)

Die Lücke, die wir hinterlassen, ersetzt uns vollkommen (Carl Heinz Schroth)

What Max,

The cow has a good point, but it is complex and I can't explain it well.
It has been discussed fairly extensively in recent threads. I suggest that
you search for threads in the last year which discuss "relativistic mass".
The executive summary is that the idea of relativistic mass is misleading
at best and incorrect at worst, so use of the term "rest mass" is preferred
to distinguish it from the relativistic effect. The Lorentz transforms are
correct, but inadequate to describe effects involving gravity and mass.

If I recall correctly, Ken G and publius were principals in the discussion.

-- Jeff, in Minneapolis

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http://www.FreeMars.org/jeff/

"The other planets?
Well, they just happen to be there, but the point of rockets is to explore them!"
-- Kai Yeves

Any physics book that talks about relativity.

Could you show me where mass (m) enters Lorentz transform?

__________________
If everyone had even a basic grasp of scientific principles, this planet would be a better place (Phil Plait)

Die Lücke, die wir hinterlassen, ersetzt uns vollkommen (Carl Heinz Schroth)

Exactly, and that´s why I said the textbooks should be rewritten.

__________________
If everyone had even a basic grasp of scientific principles, this planet would be a better place (Phil Plait)

Die Lücke, die wir hinterlassen, ersetzt uns vollkommen (Carl Heinz Schroth)

oh christ,