Our Universe as a Laboratory for Understanding Physical Laws
Uploaded by hawk18 on May 06, 2004
Cosmology is the study of the origin, current state, and future of our Universe. With recent technological advances, we have been able to probe deeper and deeper into the large scale structure of the vast universe and the small scale structure of matter. Our basis of understanding and determining fundamental physical laws in assumed to be correct when measured locally in laboratory experiments. These laws are verified over and over again so that they can be extrapolated to a distant time and place where they can be investigated with modern astronomical methods. The universe is basically used as a massive laboratory. The universe as defined by Dr. Green, is "everything that can be measured now or at any time in the future." What if our current understanding of the universe is not as perfect as we believe it to be? Our just we being egocentric in assuming that the fundamental physical laws that we have determined locally can apply to the rest of the universe? I am going to discuss why our universe is the best laboratory for understanding and determining the fundamental physical laws and then I will make an argument against this premise using dark matter, dark energy, Standard Candles, and Type 1a supernovae as a basis for discussion.
A great reason why our universe is such a good laboratory is that everything is right in front of us; it is just a matter of us looking in the right direction at the right time using the right tools. A standard candle is a term used for an astronomical object, often a star, of well understood intrinsic brightness which enables us to determine cosmic distances (CAS online). If an object can be found whose luminosity you knew absolutely just from looking at it, then by comparing the apparent luminosity with the absolute luminosity, you could figure how far away it was. As the light from a distant object travels to Earth through an expanding universe, the cosmic expansion stretches the distances between galaxy clusters and the wavelengths of the photons emitted from the object. By the time the light reaches us, the spectral wavelength will have been redshifted by exactly the same factor that the universe had been stretched in the time interval since the light left the source. In order to get the time interval, the speed of light (3*10^8 meters/second) must be multiplied by the object's distance...