Recent content by utku

Thanks Bill_K, Your answer is very usefull for me. I understood many of your reply :)

Thanks Bill_K, Can you express more explicitly the term 3-parameters and 4-parameters groups please? thanks.

Thanks to all. I search the forum and find very usefull answers to many questions about cosmology. I think before make new reply ı must search the forum:) 2- yes, i calculate George Jones, and it must depend a^(-4).

Thanks for your reply. I think you want to say homogeneous and anisotropic spaces.

What are main differencies between Bianchi models and Kantowski-Sachs models. Can anyone give mathematical definition clearly and possibly simple form?

Thanks for your reply Simon Bridge and Yogi,Chalnoth. I will look the article that Chaltoth send. Some Energy of the radiation loses due to the expansion. What is this energy transform to?

Finding a constant in an axpanding univarse Hi, I want to obtain a constant that proportional to total matter density of universe. Let ρ be matter densitiy and ρr be radiation desity. In an expanding universe volume times total density must be constant. It is wrong? let me show it...

Physic is description of nature as possible as it can.Physicists try building appropriate models for to explain how nature works.If you want read poem of nature it must be usefull learn fundamental concepts of math.Because math is language of physic, without it nature probable don't show you...

Hi,xzibition8612. Multiply both side of equatlity (1) x=ucos(theta)-vsin(theta) with cos(theta) and both of equality y=ucos(theta)...with sin(theta) you will see some terms will vanish.And you will get your answer...

a) velocity of mass 0.49 is 0.23 m/s velocity of mass 0.25 is 3.2 m/s

T1/sin40=T2/sin60=T3/sin 80 you can work out the T3 tension from this equality.and it is easily seen from figure mass m equals T3.

Hi friends. In schwarzchild vacuum solition spacetime metric singularity exist when you put the r=2gm (also called schwarzhild radius),when we use Eddington-Finkelstein coordinat we can see this singularity is depend the coordinat.So it is not real singularity. When we transform our coordinat...

In General relativity,there arent any forces,there are curvature because of the matter and energy. In special relativity valid only inertial frames.So it doenst include any gravitational force or acceleration.After,Special relativity was generalized by einstein with constracting the general...

Did you look any course book or text ? in that link there are several mathematical formulations of spin calculations. link: http://en.wikipedia.org/wiki/Spin_quantum_number"

In quantum mechanics,All particles have 4 quantum number.And these quantum numbers explain some structure of particles. for instance: principle quantum number (n):this quantum number is related to the orbit of electron around the proton and it is related to the energy of states. angular momentum...