Discussion Overview
The discussion centers around the proposal of using atomic clocks for gravitational wave detection, comparing it to existing methods like pulsar timing experiments and eLISA. Participants explore the potential sensitivity and frequency range of this new approach, as well as its feasibility and implications for detecting gravitational waves from various astronomical sources.
Discussion Character
- Exploratory
- Technical explanation
- Debate/contested
- Mathematical reasoning
Main Points Raised
- Some participants note that the proposed atomic clock method could offer a less expensive alternative to LIGO by utilizing satellites for a wider baseline.
- There are requests for comparisons of sensitivity and frequency range between the atomic clock proposal and eLISA, with some suggesting that the two may not be directly comparable due to differing target sources.
- A participant mentions querying an expert about the potential for detecting gravitational waves from inflation, indicating that while possible, such detection would be more challenging than from supermassive black holes.
- Concerns are raised regarding the relationship between baseline distance and frequency range, with one participant questioning whether frequency ranges have a proportional dependence on arm length.
- Another participant emphasizes that signal sensitivity does not necessarily correlate with measurement sensitivity, indicating uncertainty in the proposed relationships.
- There is a suggestion that the authors of the atomic clock proposal should provide standard sensitivity plots to clarify their claims.
- One participant discusses the expected frequency range for the atomic clock method, suggesting it could access lower frequencies than eLISA, but acknowledges the need for more detailed design to estimate sensitivity accurately.
- A mention of gamma wavelengths and their potential for high resolution in detecting velocity changes raises questions about the existence and feasibility of coherent gamma sources for this application.
Areas of Agreement / Disagreement
Participants express a range of views on the feasibility and implications of the atomic clock proposal, with no consensus reached on its effectiveness compared to existing gravitational wave detection methods. Uncertainties regarding the relationships between baseline distance, frequency range, and sensitivity remain prominent in the discussion.
Contextual Notes
Participants highlight limitations in the current understanding of the proposed method's sensitivity estimates and the need for further detailed design work. There are also unresolved questions regarding the dependence of frequency ranges on arm lengths and the potential for coherent gamma sources.