Redshift is a phenomenon in physics, especially astrophysics
Redshift or red shift may also refer to:
In physics and general relativity, gravitational redshift is the phenomenon that electromagnetic waves or photons travelling out of a gravitational well lose energy. This loss of energy corresponds to a decrease in the wave frequency and increase in the wavelength, known more generally as a redshift. The opposite effect, in which photons gain energy when travelling into a gravitational well, is known as a gravitational blueshift. The effect was first described by Einstein in 1907, eight years before his publication of the full theory of relativity.
In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation. The opposite change, a decrease in wavelength and increase in frequency and energy, is known as a blueshift, or negative redshift. The terms derive from the colours red and blue which form the extremes of the visible light spectrum. The main causes of electromagnetic redshift in astronomy and cosmology are the relative motions of radiation sources, which give rise to the relativistic Doppler effect, and gravitational potentials, which gravitationally redshift escaping radiation. All sufficiently distant light sources show cosmological redshift corresponding to recession speeds proportional to their distances from Earth, a fact known as Hubble's law that implies the universe is expanding.
Singularity or singular point may refer to:
Red Queen may refer to:
The relativistic Doppler effect is the change in frequency, wavelength and amplitude of light, caused by the relative motion of the source and the observer, when taking into account effects described by the special theory of relativity.
Watchdog or watch dog may refer to:
Shift may refer to:
Halton Christian "Chip" Arp was an American astronomer. He is remembered for his 1966 book Atlas of Peculiar Galaxies, which catalogued unusual looking galaxies and presented their images.
Echoes may refer to:
Tired light is a class of hypothetical redshift mechanisms that was proposed as an alternative explanation for the redshift-distance relationship. These models have been proposed as alternatives to the models that involve the expansion of the universe. The concept was first proposed in 1929 by Fritz Zwicky, who suggested that if photons lost energy over time through collisions with other particles in a regular way, the more distant objects would appear redder than more nearby ones.
The face is a part of the body, the front of the head.
Tests of general relativity serve to establish observational evidence for the theory of general relativity. The first three tests, proposed by Albert Einstein in 1915, concerned the "anomalous" precession of the perihelion of Mercury, the bending of light in gravitational fields, and the gravitational redshift. The precession of Mercury was already known; experiments showing light bending in accordance with the predictions of general relativity were performed in 1919, with increasingly precise measurements made in subsequent tests; and scientists claimed to have measured the gravitational redshift in 1925, although measurements sensitive enough to actually confirm the theory were not made until 1954. A more accurate program starting in 1959 tested general relativity in the weak gravitational field limit, severely limiting possible deviations from the theory.
The Pound–Rebka experiment monitored frequency shifts in gamma rays as they rose and fell in the gravitational field of the Earth. The experiment tested Albert Einstein's 1907 and 1911 predictions, based on the equivalence principle, that photons would gain energy when descending a gravitational potential, and would lose energy when rising through a gravitational potential. It was proposed by Robert Pound and his graduate student Glen A. Rebka Jr. in 1959, and was the last of the classical tests of general relativity to be verified. The measurement of gravitational redshift and blueshift by this experiment validated the prediction of the equivalence principle that clocks should be measured as running at different rates in different places of a gravitational field. It is considered to be the experiment that ushered in an era of precision tests of general relativity.
In astronomy, a blueshift is a decrease in electromagnetic wavelength caused by the motion of a celestial object toward an observer.
The history of the Big Bang theory began with the Big Bang's development from observations and theoretical considerations. Much of the theoretical work in cosmology now involves extensions and refinements to the basic Big Bang model. The theory itself was originally formalised by Father Georges Lemaître in 1927. Hubble's law of the expansion of the universe provided foundational support for the theory.
Red Room may refer to:
A straw man is a form of argument and an informal fallacy.
Amazon Redshift is a data warehouse product which forms part of the larger cloud-computing platform Amazon Web Services. It is built on top of technology from the massive parallel processing (MPP) data warehouse company ParAccel, to handle large scale data sets and database migrations. Redshift differs from Amazon's other hosted database offering, Amazon RDS, in its ability to handle analytic workloads on big data data sets stored by a column-oriented DBMS principle. Redshift allows up to 16 petabytes of data on a cluster.
Red Shadow, or Akakage, is a Japanese ninja character.
The Hyperion proto-supercluster is the largest and earliest known proto-supercluster, 5,000 times the mass of the Milky Way and seen at 20% of the current age of the universe. It was discovered in 2018 by analysing the redshifts of 10,000 objects observed with the Very Large Telescope in Chile.