Gravitational waves - second question

In summary, Gravitational waves are not currently detectable, likely because the influence of gravity is too small to be detected.
  • #1
tonyb1969
8
0
Gravitational "waves" - second question

Assuming our concept of the universe expanding (perhaps) and that the fabric of space time is expanding at the same rate as our galaxy and solar system (velocity equal, so relatively motionless), would we still be able to detect gravitational waves when a planet (Earth, for example) accelerates around the Sun?
 
Physics news on Phys.org
  • #2


Your question includes internal inconsistencies and I have no idea what "velocity equal so relatively motionless" means.

Our galaxy is NOT expanding to any appreciable nor measureable degree. Only at (great) cosmological distances is dark energy (the cosmological constant) large enough to over come gravity and enable spacetime to expand. At ginormous distances from us, galaxies are receding at greater than the speed of light and hence gravitational waves from those galaxies will never reach us., nor will anything else; locally gravitational waves should always reach us unless the cosmological contant grows in the future to such a degree that, say, the sun and Earth move away from each other at greater than light speed.

If that doesn't not make enough sense try wikipedia at

http://en.wikipedia.org/wiki/Observable_universe

and note other wiki sources to the right under the box PHYSICAL COSMOLOGY. Beware "horizons" in cosmology are not immediately obvious.
 
  • #3


While I personally like the idea of an ether, most say the "fabric of space" is just a metric. I would think the influence of gravity is present from any matter in the observable universe but in most cases would be too small to detect. Naty1 did well pointing out if you can't see the light, you will not feel the gravity.
 
  • #4


Sincere thanks for overcoming the naive challenge of my question (I was having a hard time knowing how to word it). Your explanation, though, did answer what I was trying to get at. I'll also look on wikipedia as suggested...thanks...
 

Related to Gravitational waves - second question

1. What are gravitational waves?

Gravitational waves are ripples in the fabric of space-time that are caused by the acceleration of massive objects, such as black holes or neutron stars. They were predicted by Albert Einstein's theory of general relativity and were first detected in 2015.

2. How are gravitational waves detected?

Gravitational waves are detected using highly sensitive instruments called interferometers, which measure tiny changes in the distance between two objects caused by the passing of a gravitational wave. These instruments use lasers and mirrors to detect the ripples in space-time.

3. What does the detection of gravitational waves mean for science?

The detection of gravitational waves has opened up a new field of astronomy and has allowed scientists to study and understand the universe in a completely new way. It also provides further evidence for Einstein's theory of general relativity and has the potential to reveal new insights about the nature of space and time.

4. Can gravitational waves be used for practical purposes?

At this point in time, gravitational waves are not being used for practical purposes. However, scientists are exploring the possibility of using them for space-based navigation and communication systems in the future.

5. Are there different types of gravitational waves?

Yes, there are three different types of gravitational waves: continuous waves, burst waves, and stochastic background. Continuous waves are emitted by objects with stable orbits, burst waves are short-lived and result from violent events such as supernovae, and stochastic background is a random and constant background of gravitational waves in the universe.

Similar threads

  • Special and General Relativity
Replies
4
Views
1K
  • Special and General Relativity
Replies
6
Views
1K
  • Special and General Relativity
Replies
24
Views
1K
  • Special and General Relativity
Replies
11
Views
543
  • Special and General Relativity
Replies
5
Views
1K
  • Special and General Relativity
Replies
3
Views
897
  • Special and General Relativity
Replies
5
Views
895
  • Special and General Relativity
Replies
11
Views
1K
  • Special and General Relativity
Replies
11
Views
2K
  • Special and General Relativity
Replies
4
Views
1K
Back
Top