Related Experiment Video
Updated: Aug 5, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Cross correlation of the cosmic microwave background with radio sources: constraints on an accelerating universe
1Department of Astronomy, Haverford College, Haverford, Pennsylvania 19041, USA.
Abstract:
We present a new limit on the cosmological constant based on the absence of correlations between the cosmic microwave background (CMB) and the distribution of distant radio sources. In cosmological constant, cold dark matter ( LambdaCDM) models, such correlations should have been produced via the integrated Sachs-Wolfe effect, assuming that radio sources trace the local ( z approximately 1) matter density. We find no evidence of correlations and obtain a 95% C.L. upper limit on the cosmological constant of Omega(Lambda)< or =0.74. If 0.6
Related Concept Videos
Schwarzschild Radius and Event Horizon
The minimum speed required to launch a projectile from the surface of an object to which it is gravitationally bound so that it eventually escapes the object’s gravitational field is called the escape velocity. The escape velocity is independent of the mass of the object. Merging the idea of escape velocity with the...
Detection of Black Holes
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
Space-Time Curvature and the General Theory of Relativity
This has been verified in many experiments. However, space and time are no longer absolute. Two observers moving relative to one another do not agree on the length of objects or the passage of time. The mechanics of objects based on Newton's laws of motion,...
Atomic Nuclei: Larmor Precession Frequency
Divergence and Curl of Magnetic Field
Real-World Applications of Space Curves

