Do the Sachs-Wolfe and Rees-Sciama Effects Influence Matter?

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TL;DR Summary
Can the integrated Sachs-Wolfe and the Rees-Sciama effects have any influence on matter? For example influencing the orbits of celestial bodies in cluster & voids?
CMB photons can be affected by the expansion of the universe through the linear integrated Sachs-Wolfe effect (ISW) [1] and the non-linear ISW effect or also called Rees-Sciama effect [1].

In particular, according to the ISW effect, the photons crossing superclusters would leave them having a total net blueshift (because of the gravitational potential decay of the cluster) while crossing a supervoid would leave them with a total net redshift (all compared to the overall redshift from the universe's expansion itself)

The Rees-Sciama effect on the other hand, "cools" a bit the photons crossing both structures but "heats" them to those that travel near the outskirts of both superclusters and supervoids [2]


However, we are always talking about photons here. Do these effects also affect matter (or particles with mass) in any manner? For instance, since gravitational potentials are related to these effects, shouldn't that have some kind of influence for particles with mass as well (and not only masless particles, like photons)? Can these effects affect the orbits of celestial bodies in clusters and voids, for instance?



[1]: https://en.wikipedia.org/wiki/Sachs–Wolfe_effect

[2]: https://www.roe.ac.uk/~cai/index_ISW.html
 

FAQ: Do the Sachs-Wolfe and Rees-Sciama Effects Influence Matter?

What are the Sachs-Wolfe and Rees-Sciama effects?

The Sachs-Wolfe effect refers to the redshift of cosmic microwave background (CMB) photons as they travel through gravitational potential wells. The Rees-Sciama effect is a secondary anisotropy in the CMB caused by the time-evolution of gravitational potentials due to the large-scale structure of the universe.

How do these effects influence the Cosmic Microwave Background (CMB)?

The Sachs-Wolfe effect causes temperature fluctuations in the CMB due to gravitational redshift. The Rees-Sciama effect further modifies these fluctuations by altering the gravitational potentials as structures like galaxies and clusters evolve over time. Both effects contribute to the anisotropies observed in the CMB.

Do the Sachs-Wolfe and Rees-Sciama effects directly impact the distribution of matter in the universe?

No, the Sachs-Wolfe and Rees-Sciama effects primarily influence the CMB photons rather than the distribution of matter. However, they provide insights into the gravitational potentials created by matter, thus indirectly informing us about the matter distribution.

Can the Sachs-Wolfe and Rees-Sciama effects be observed separately?

Distinguishing between the Sachs-Wolfe and Rees-Sciama effects can be challenging because they both contribute to the anisotropies in the CMB. However, the Sachs-Wolfe effect is more prominent on large scales, while the Rees-Sciama effect becomes significant on smaller scales and in regions with evolving gravitational potentials.

What role do these effects play in cosmology?

The Sachs-Wolfe and Rees-Sciama effects are crucial for understanding the early universe and the evolution of large-scale structures. They help cosmologists test theories of gravity, measure the universe's expansion rate, and study the distribution and evolution of matter and dark energy.

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