Recent content by mapsread

Hi Swamp Thing, Thanks for your response. It is problem 70.9 from Exercises for the Feynman Lectures On Physics, The New Millennium Edition. I looked around the web, but could not find the problem in e-form (not surprisingly, it's probably copyrighted). The answer in the back refers to some...

Greetings, Apparently the first measurement of the diameter of a star other than the Sun was done using quantum mechanics -- specifically, the Hanbury Brown and Twiss effect. If one has two detectors, then there are distinguishable and indistinguishable interactions with photons from the star...

Yes, we posted at the same time. Thanks for your very thorough responses!

I mean HORIZONTAL (in the direction of travel). At any rate, I understand now. :-)

Yes, I was getting hung up on vertical length contraction. However, I see what you mean now; it just doesn't come into play. Thanks again.

Thank you, that's exactly what I wanted to know. Incidentally, is the time dilation derived from the length contraction? I'm not quite sure which to apply. If you have two points I and J on the surface of the Earth in the direction of B's travel, then E and B do disagree on how far apart they...

Yes, Hawking radiation is what I was referring to. I forgot which forum I was in.

One of the very defining characteristics of a black hole is its mass, and all the laws of nature appear to be set up to prevent what you are suggesting -- that the mass move away from the black hole (quickly. That is, in some manner other than Hawking radiation). It's not an experimental...

Greetings all, Taken in the limit of a small distance where the Earth appears flat, does a stationary object (relative to the Earth) disagree with an object moving horizontally about the force due to gravity, g? (Again, take the limit of having no altitude, so g is constant.) For example, the...

I don't think I've ever been so happy to have made a math error! Well, actually, I set up my integral wrong, but that's about the same. The weird thing is that I wrote a simple program to double-check, that also had an error, but for a different reason and gave me a similarly wrong answer! I was...

Thank you. At first I was thinking it doesn't do much good to have to know about the answer beforehand if you're trying to derive it. In thinking about it more, however, I guess you only have to know the start and end points and then you essentially solve for the whole thing at once. At any...

Greetings, Thanks for your answers. I'm not sure I was clear in my original post. I'm trying to determine the basis or most fundamental principle associated with the principle of least action (or stationary action). The laws of motion can be derived from that principle. Since they can be...

Greetings, I'm simulating the principle of least action for simple object motion and reading from Feynman Vol. 2, Chpt 19 -- The Principle of Least Action. He states (with my paraphrasing) that the true path of a trajectory is the one for which the integral over all points of kinetic energy...