“Strong, weak and electromagnetic interaction are evidently part of a grand unified theory. These temperatures are today quite inaccessible. They were achieved only in the earliest moments of the Big Bang. Since then, the universe has congealed, losing its symmetry.”

—  Sheldon L. Glashow

Source: The Charm of Physics (1991), p. 244

Adopted from Wikiquote. Last update June 3, 2021. History

Help us to complete the source, original and additional information

Do you have more details about the quote "Strong, weak and electromagnetic interaction are evidently part of a grand unified theory. These temperatures are today…" by Sheldon L. Glashow?
Sheldon L. Glashow photo
Sheldon L. Glashow 5
American theoretical physicist 1932

Related quotes

Frank Wilczek photo

“If grand unified theories are correct, we ought to be able to derive the relative power of the strong, weak, and electromagnetic interactions at accessible energies from their presumed equality at much higher energies. When this is attempted, a wonderful result emerges. …in the form first calculated by Howard Georgi, Helen Quinn, and Steven Weinberg …The couplings of strong-interaction gluons decrease, those of the [weak interaction] W bosons stay roughly constant, and those of the [electromagnetic interaction] photons increase at short distances [or high energies]—so they all tend to converge, as desired.”

Frank Wilczek (1951) physicist

Longing for the Harmonies: Themes and Variations from Modern Physics (1987)

Alan Guth photo

“A very plausible choice for when inflation might have happened would be when the energy scales of the universe were at the scale of grand unified theories… which unify the weak, strong and electromagnetic interactions into a single unified interaction... we're talking about energies which are about 1016 times the equivalent energy of a proton mass. …the initial patch would only have to be the ridiculously small size of about 10-28 cm across to be able to lead ultimately to the creation of everything that we see on the vast scale of which we see it.”

Alan Guth (1947) American theoretical physicist and cosmologist

Lecture 1: Inflationary Cosmology: Is Our Universe Part of a Multiverse? Part I.
The Early Universe (2012)

Steven Weinberg photo

“One of the things that excited me so much about quantum chromodynamics after the work of Gross and Wilczek and Politzer was that it seemed to provide a rational explanation for what had always been mysterious to me — the fact that there were symmetries, like parity conservation, charge conjugation invariance, and strangeness conservation, that were very good symmetries of the strong and electromagnetic interactions — as far as we knew exact — and yet were not respected by the weak interactions. Why should nature have … symmetries that are symmetries of part of nature but not other parts of nature?”

Steven Weinberg (1933) American theoretical physicist

"Reminiscences of the Standard Model" - Special Colloquium by Steven Weinberg https://www.youtube.com/watch?v=mX2R8-nJhLQ, 17 October 2017, YouTube video at 1:02:17 of 1:39:24

Alan Guth photo

“The conventional Big Bang theory does not say anything about what caused the expansion. It really is only a theory about the aftermath of a bang. In the scientific version of the Big Bang, the universe starts with everything already expanding, with no explanation of how that expansion started… So the Scientific version of the Big Bang theory is not really a theory of a bang, it's really a theory of the aftermath of a bang.”

Alan Guth (1947) American theoretical physicist and cosmologist

Lecture 1: Inflationary Cosmology: Is Our Universe Part of a Multiverse? Part I.
The Early Universe (2012)

Leonard Susskind photo

“The standard SU(3)×SU(2)×U(1) theory of strong, electromagnetic, and weak interactions appears to correctly describe physics down to the smallest distance scales yet probed.”

Leonard Susskind (1940) American physicist

[1984, The gauge hierarchy problem, technicolor, supersymmetry, and all that, Physics Reports, 104, 2–4, 181–193, 10.1016/0370-1573(84)90208-4]

Jayant Narlikar photo

“…mention is made of evidences in favour of the big bang, like the microwave background. It is a relic radiation supposed to have formed very early after the big bang. As the universe expanded it cooled down and its present temperature is at 2.7 K. The only fact which is measurable or has been measured is that there is a background of 2.7 K temperature. Saying that this is left over from the early universe is a speculation. It is a part of a theoretical structure I am supposed to have built which enables me to say that it is a relic of that early-on era. We have given a different explanation. Helium forms by fusion of hydrogen inside a star like the sun, leading to radiation. One can ask the following question: if all the helium that you find in the universe was formed in stars sometime or the other, how much radiation will be formed and what would its temperature be? The answer is 2.7 K. If you ask a big bang person why his relic radiation today has a temperature of 2.7 K he doesn’t know. This alternative explanation that I’m giving is able to do more than what the big bang does. So I don’t see any reason to say we have a very positive proof of the big bang happening.”

Jayant Narlikar (1938) Indian physicist

Jayant Narlikar's Cosmology

Brian Greene photo

“Some people think that the big bang is an explanation of how the universe began, its not. The big bang is a theory of how the universe evolved from a split second after whatever brought it into existence.”

Brian Greene (1963) American physicist

In response to David Letterman's question, "What do we now know [about the universe] we didn’t know before?" on The Late Show (23 March 2005)
Context: Well, a big question is how did the universe begin. And we, cannot answer that question. Some people think that the big bang is an explanation of how the universe began, its not. The big bang is a theory of how the universe evolved from a split second after whatever brought it into existence. And the reason why we’ve been unable to look right back at time zero, to figure out how it really began; is that conflict between Einstein’s ideas of gravity and the laws of quantum physics. So, string theory may be able to — it hasn’t yet; we’re working on it today — feverishly. It may be able to answer the question, how did the universe begin. And I don’t know how it’ll affect your everyday life, but to me, if we really had a sense of how the universe really began, I think that would, really, alert us to our place in the cosmos in a deep way.

Alan Guth photo

“Inflation is a prequel to the conventional Big Bang theory. …It does provide a theory of the propulsion that drove the universe into this humungous episode of expansion which we call the Big Bang.”

Alan Guth (1947) American theoretical physicist and cosmologist

Lecture 1: Inflationary Cosmology: Is Our Universe Part of a Multiverse? Part I.
The Early Universe (2012)

Jayant Narlikar photo

“Found that in a universe that is expanding after a big bang event, neutrinos would turn up at a detector before they were emitted. Only future-going neutrinos were possible in the Steady state cosmology while the ever-expanding big bang models gave neutrinos travelling into Steady State theory to the past.”

Jayant Narlikar (1938) Indian physicist

Neutrino misbehaviour suggested 50 years ago

David Gross photo

“The universe has been expanding since the big bang, thus early on it was hot and dense. To trace the history of the universe we must understand the dynamics that operates when the universe was hot and particles were very energetic. Before the standard model we could not go back further than 200,000 years after the big bang. Today, especially since QCD simplifies at high energy, we can extrapolate to very eary times, where nucleons melt and quarks and gluons are liberated to form a quark-gluon plasma.”

David Gross (1941) American particle physicist and string theorist

"The Discovery of Asymptotic Freedom and the Emergence of QCD" http://www.nobelprize.org/nobel_prizes/physics/laureates/2004/gross-lecture.html, Nobel Lecture, p. 79, nobelprize.org (2004)

Related topics