How electromagnetic stellar gravity waves (GR) form the effects of sound waves at the LIGO observatory?

In summary, the conversation discusses the use of sound waves to detect gravitational waves at the LIGO observatory and the connection between gravity and electromagnetic waves. It also mentions the work of Weber in detecting gravitational waves using an aluminum beam, but notes that sound waves cannot propagate in the vacuum of stellar space.
  • #1
carl susumu
17
0
https://en.wikipedia.org/wiki/LIGO#/media/File:Simplified_diagram_of_an_Advanced_LIGO_detector.png

The axis on the bottom of the graph depicts frequencies between 20-1000 Hz which are sound waves. Again, how can a sound wave (gravity waves) propagate in the near vacuum of stellar space that is vacuum?

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

"On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0×10^−21." (Abstract).Abbott, B. P. Observation of Gravitational Waves from a Binary Black Hole Merger. Physical Review Letters. 116, 061102. 2016

---------------------------------------------------------------------------------------------------------------------------------

Can you explain how electromagnetic stellar gravity waves (GR) form the effects of sound waves at the LIGO observatory?
 
Astronomy news on Phys.org
  • #2
carl susumu said:
The axis on the bottom of the graph depicts frequencies between 20-1000 Hz which are sound waves. Again, how can a sound wave (gravity waves) propagate in the near vacuum of stellar space that is vacuum?

Sound waves which are audible to us have frequencies from about 20-20,000 Hz, but other waves exist with these frequencies which are not sound waves. For example, EM waves at this frequency are used for communications.

As for what these gravitational waves use as a medium, the answer is that they are waves in the metric of spacetime. They are, in short, a propagating temporary change in the geometry of spacetime.

carl susumu said:
Can you explain how electromagnetic stellar gravity waves (GR) form the effects of sound waves at the LIGO observatory?

These waves are gravitational waves. Gravity waves, electromagnetic waves, and sound waves are all something different. Gravity waves are waves on the surface of a fluid, such as the wave on the surface of the ocean, while EM waves are waves in the electromagnetic field (light, radio waves, x-rays, etc) and sound waves are a certain type of wave within a physical medium such as water, air, or even rock.
 
  • #3
In Einstein's paper, "The Foundation of the Generalised Theory of Relativity" (1916), Einstein represents gravity with Maxwell's electromagnetic field using Maxwell's equations.

dh/dt + rot e = 0.........70div h = 0............71rot h - de'/dt = i.........72div e' = p"..........73

(Einstein5, § 20). Einstein is representing gravity with Maxwell's electromagnetic field that is based on Faraday's induction effect but a small stone that is affected by gravity yet unaffected by a magnet of Faraday's law and a three inch lead plate does not produce anti-gravity which proves gravity is not an electromagnetic phenomenon. Stellar gravity waves are electromagnetic waves. The same waves as a radio wave.
 
  • #4
Weber experimentally detected gravitational waves that have the frequency of sound (1662 Hz). "Further advances are necessary in order to generate and detect gravitational waves in the laboratory." (Weber, Conclusion, 1960). "A description is given of the gravitational radiation experiments involving detectors at opposite ends of a 1000 kilometer baseline, at Argonne National Laboratory and the University of Maryland. Sudden increases in detector output are observed roughly once in several days, coincident within the resolution time of 0.25 seconds. The statistics rule out an accidental origin and experiments rule out seismic and electromagnetic effects. It is reasonable to conclude that gravitational radiation is being observed." (Weber, Abstract, 1970). "EXPERIMENTS AT 1662 HERTZ" (Weber, Intro, 1970).Weber detected gravity waves with the frequency of 1662 Hz using the acoustical vibration of a 750 lb aluminum beam but sound cannot propagate in the vacuum of stellar space.
 
  • #5
Precedence--------Weber
 
  • #6
carl susumu said:
In Einstein's paper, "The Foundation of the Generalised Theory of Relativity" (1916), Einstein represents gravity with Maxwell's electromagnetic field using Maxwell's equations.

No he isn't. To quote Einstein, from paragraph 814 on his translated paper at wikisource:

The equations (60), (62) and (63) give thus a generalisation of Maxwell's field-equations in vacuum, which remains true in our chosen system of co-ordinates.

He's setting up Maxwell's equations in a form which remains invariant regardless of your coordinate system choice.

carl susumu said:
Stellar gravity waves are electromagnetic waves.

That is incorrect.

carl susumu said:
Weber detected gravity waves with the frequency of 1662 Hz using the acoustical vibration of a 750 lb aluminum beam but sound cannot propagate in the vacuum of stellar space.

The "acoustical vibration" is in the aluminum beam, which is being stressed at the frequency of the passing of the gravitational wave (or would be if he had actually detected a gravitational wave, which he did not), it is not in the vacuum. No sound is propagating through space.
 

1. What are LIGO gravity waves?

LIGO (Laser Interferometer Gravitational-Wave Observatory) is a scientific experiment designed to detect gravitational waves. These are ripples in the fabric of space-time caused by massive objects accelerating, such as black holes or neutron stars.

2. How does LIGO detect gravity waves?

LIGO uses a system of two identical detectors located in different parts of the United States. Each detector consists of two 4 km long arms arranged in an L-shape. When a gravitational wave passes through the detectors, it causes tiny changes in the lengths of the arms, which are measured by lasers.

3. Why is LIGO important for science?

LIGO's detection of gravitational waves in 2015 provided the first direct evidence of the existence of these waves, confirming a major prediction of Einstein's theory of general relativity. This has opened up a whole new field of astronomy, allowing us to study some of the most extreme and violent events in the universe.

4. What are some potential applications of LIGO's discoveries?

LIGO's discoveries have the potential to improve our understanding of the universe, including the formation and evolution of black holes and neutron stars. They could also lead to new technologies, such as more precise clocks and improved GPS systems. Additionally, LIGO's technology could be adapted for other fields, such as medicine and engineering.

5. Are there any other gravity wave detectors besides LIGO?

Yes, there are other detectors currently in operation or under development, such as Virgo in Italy, KAGRA in Japan, and the planned space-based detector LISA. These detectors complement LIGO's capabilities and help scientists gather more information about gravitational waves and their sources.

Similar threads

  • Astronomy and Astrophysics
Replies
19
Views
4K
  • Special and General Relativity
Replies
7
Views
2K
  • Special and General Relativity
Replies
8
Views
2K
  • Special and General Relativity
Replies
15
Views
3K
Replies
5
Views
1K
Replies
20
Views
5K
  • Special and General Relativity
2
Replies
66
Views
5K
  • Special and General Relativity
Replies
2
Views
1K
  • Special and General Relativity
Replies
2
Views
1K
  • Beyond the Standard Models
Replies
11
Views
2K
Back
Top