Does Gravity Travel at the Speed of Light? (1998)

#1

Post by jonbaer » Wed, Aug 21, 2013, 5:48 PM UTC

Does Gravity Travel at the Speed of Light? (1998)
math.ucr.edu

Re: Does Gravity Travel at the Speed of Light? (1998)

#2

Post by spdegabrielle » Wed, Aug 21, 2013, 6:12 PM UTC

Don't 'TL;DR' this is worth reading.

Re: Does Gravity Travel at the Speed of Light? (1998)

#3

Post by ssivark » Wed, Aug 21, 2013, 6:24 PM UTC

It's a fairly short and clear article, so no need for a Tl;DR. Note that this is NOT yet another "revolutionary" announcement, but just contemplative reasoning from a respected expert in gravitational physics.

Re: Does Gravity Travel at the Speed of Light? (1998)

#4

Post by gtani » Wed, Aug 21, 2013, 6:25 PM UTC

Baez has published some great booklists and a FAQ for self study

http://math.ucr.edu/home/baez/physics/index.html

http://math.ucr.edu/home/baez/books.html

http://math.ucr.edu/home/baez/physics/Administrivia/booklist...

Re: Does Gravity Travel at the Speed of Light? (1998)

#5

Post by mladenkovacevic » Wed, Aug 21, 2013, 6:30 PM UTC

I wonder if the recent nova event visible with the naked eye can be used to do an experimental measurement... or perhaps it has to be a supernova as the article suggests.

Re: Does Gravity Travel at the Speed of Light? (1998)

#6

Post by codezero » Wed, Aug 21, 2013, 6:42 PM UTC

mladenkovacevic wrote: post #5

I wonder if the recent nova event visible with the naked eye can be used to do an experimental measurement... or perhaps it has to be a supernova as the article suggests.

I am guessing it has to be a supernova on account of there being many novae discovered/observed each year.

Re: Does Gravity Travel at the Speed of Light? (1998)

#7

Post by chiph » Wed, Aug 21, 2013, 7:07 PM UTC

So, the FTL gravity pulses used in David Weber's Honorverse series (sci-fi space opera) aren't possible. :(

Re: Does Gravity Travel at the Speed of Light? (1998)

#8

Post by yawgmoth » Wed, Aug 21, 2013, 7:24 PM UTC

Something very interesting whenever this question is asked - what is the speed of light? It is "the speed at which data propagates through space time". I think that is a fascinating truth to our universe.

There is a very good discussion from r/askscience on this topic: http://www.reddit.com/r/askscience/comments/1kjp6z/does_grav...

Re: Does Gravity Travel at the Speed of Light? (1998)

#9

Post by chockablock » Wed, Aug 21, 2013, 7:45 PM UTC

Date in title should be 2011 (date of latest revision), not 1998. Article includes a citation from after 1998.

Re: Does Gravity Travel at the Speed of Light? (1998)

#10

Post by pdonis » Wed, Aug 21, 2013, 7:50 PM UTC

mladenkovacevic wrote: post #5

I wonder if the recent nova event visible with the naked eye can be used to do an experimental measurement... or perhaps it has to be a supernova as the article suggests.

Yes, any gravitational radiation from a nova would be much weaker than from a supernova. As the article notes, unless the supernova is very close to us, our current detectors can't detect the gravitational waves from a supernova, so they certainly wouldn't be able to pick them up from a nova.