Natural Science Forum / Physics / Research / June 2008

Dear Igor (or anyone else who wants to give it a try):
I have a few questions with reference to a thread that you participated
in some time ago, at:
http://www.physicsforums.com/archive/index.php/t-142092.html or

It is often said, that entropy is the average number of yes-no
questions you have to ask to obtain the information "which event"
occurred.
In Honerkamp "Statistical Physics An Advanced Approach with

I'm trying to get the correct definition of Minkowski spacetime. I
have basically five different (looking) definitions and I'm wondering
which one is correct or whether they are equivalent perhaps?
1. a d-dimensional vector space with a lorentz, ie (d-1,1) signature,

A friend of mine raised the question as to what the
current theory is about how stars "ignite". That is,
how hydrogen fusion inside a star gets started. If
you have an initial huge ball of hydrogen, the hydrogen

There are 3 types of heat -- radiant, conductive, and convective.
The quantum of radiant heat [which is basically EM radiation] is the photon.
The quantum of conductive heat is the phonon.
What is the quantum of convective heat?

Many have suggested that dark energy is the result of one or more currently
unknown quantum fields. If the dark energy quanta are approximately at rest,
relative to nearby galaxies, then could they interact with gamma ray photons
(of different energies) in such a way that it ...

hi i am a computer science student writing a computer program to
calculate the radar cross section using ray tracing. I'm simulating
the plane waves by using a set of parallel rays and i need to
calculate electric field. According to the thesis that i am following,

I don=92t understand something that is very basic. In Geometric Algebra/
Clifford Algebra I don=92t understand why the scalar in an M vector is
not considered a dimension as the vectors are.
My confusion comes from three different viewpoints, each of which show

Is MOND (Modified Newtonian Dynamics) beaten to death yet? This theory
is tried to explained dark matter without resolving to any new theory
or new physics. It basically tries to apply two different standard at
different scale of physics. If people cannot propose any consistent

When we perform a 3+1 decomposition of GR (let us assume the sppatial
part is compact without boundary to make it simpler), we obtain
something which is the so called gravitational momenta. This momentum
has two components, one is the bare metric velocity [/tex]\dot g[tex]

M.theory lives in 11 dimensions, and 7 dimensions is the minimum
dimension for a space to support an action of SU(3) x SU(2) x U(1)
Connes-Marcolli theory lives in 10 dimensions, and its extra 6
dimensional spectral triple contains the standard model.

I have quite a few questions resulting from my recent foray into the
mathematical and conceptual foundations of STR. I realise there is a
Google group devoted to this subject but, to be frank, there are only
one or two minds on that forum whose answers I have come to respect,

Subject: Re: Gravity at the Molecular Level
sci.physics.research
2008 February 18
http://groups.google.com/group/sci.physics.research/msg/baf3e2fa2ddad990?dmode=source

I am trying to decide between two view of a problem, and would like
input.
Consider the canonical commutation relationship
x^v p^u = p^u x^v  + i hbar kronecker^vu  (1)

Is it possible to make a free-electron laser that emit coherent gamma
rays? If so, could this laser be used to ignite Hydrogen-Boron fusion?
Thanks,
Radium