Gravity

Category archives for Gravity

“The fact that gravitational damping is measured at all is a strong indication that the propagation speed of gravity is not infinite.  If the calculational framework of general relativity is accepted, the damping can be used to calculate the speed, and the actual measurement confirms that the speed of gravity is equal to the speed…

“The world is the great gymnasium where we come to make ourselves strong.” -Swami Vivekananda But what does it truly mean to be strong? We have four fundamental forces in the Universe: the strong, electromagnetic, weak and gravitational forces. You might think that, by virtue of its name, the strong force is the strongest one.…

“All truths are easy to understand once they are discovered; the point is to discover them.” -Galileo Galilei Galileo is most famous for his astronomical discoveries, including the moons of Jupiter, the existence of sunspots and the phases of Venus. These discoveries were a strong challenge to geocentrism, and his writings and debates helped popularize…

“I’m here for several reason, Mr. Pepin, first of all for aid. When something tragic happens in our skies, we do our utmost to extend sympathy. But sympathy without action,that’s an empty emotion. Mainly I’m here for the purposes of reentry.” “I don’t understand.” “Adjustment,” Harold said, “to earth. I’m here to make sure you…

“If you are not completely confused by quantum mechanics, you do not understand it.” -John Wheeler Now that LIGO has detected gravitational waves directly, it’s time to examine all the different sources that they come from, and what they can teach us about the Universe. While accelerating masses in strong gravitational fields — black holes,…

“You asked me how to get out of the finite dimensions when I feel like it. I certainly don’t use logic when I do it. Logic’s the first thing you have to get rid of.” -J.D. Salinger Now that gravitational waves have been verified to exist, and the first black hole-black hole merger has been…

“If the imprint is really due to gravitational waves from the big bang, then this is the type of cosmological discovery that comes along perhaps once every fifty years.” -Kip Thorne Now that LIGO’s successfully detected it’s first gravitational waves — from two merging black holes — we know that we will find them in…

Can LIGO test Quantum Gravity? (Synopsis)

“There was a long history of speculation that in quantum gravity, unlike Einstein’s classical theory, it might be possible for the topology of spacetime to change.” -Edward Witten General relativity makes very specific prediction for what the curvature of space should be at the event horizon of a black hole, and for the consequences to…

“Ladies and gentlemen, we have detected gravitational waves.” -David Reitze More than 100 years after Einstein’s relativity came out, one of its last great predictions — the existence of gravitational radiation — has been directly experimentally confirmed! The LIGO collaboration has observed two ~30 solar mass black holes merging together, producing a slightly less massive final…

“Einstein’s gravitational theory, which is said to be the greatest single achievement of theoretical physics, resulted in beautiful relations connecting gravitational phenomena with the geometry of space; this was an exciting idea.” -Richard Feynman When we look out into the Universe, we normally gain information about it by gathering light of various wavelengths. However, there…