What is the physical significance of the dilaton in string theory?
2012年6月20日 · The dilaton field is then an essential component of all superstrings models, and thus of the cosmological scenarios based on effective string actions. Chapter 9 in Maurizios Gasperini’s String Cosmology book is a very nice introduction to dilaton phenomenology and its importance in cosmology.
quantum field theory - The difference between The Dilaton and …
Dilaton is the generic name of the Goldstone Boson (GB) associated with spontaneous breaking of scale invariance. Any model that break scale invariance spontaneously will give rise to a dilaton. N=4 SYM for example has a moduli space and any modulus away form the origin will break conformal invariance, and a massless dilaton would appear.
quantum chromodynamics - Dilaton field and Scale symmetry …
I have read at some places that a dilaton field is associated with the spontaneous breaking of scale symmetry in a theory. (While others would be difficult to trace right now, the most easily acces...
Dilaton in Background Field - Physics Stack Exchange
In this approach, you will see that the CFTs may have the term above, with a general function $\Phi(X)$ that has to obey a Klein-Gordon-like (with a potential) equation, the spacetime field equation for the dilaton field, for the 1-loop corrections to the world sheet scale invariance to cancel and everything else in the spacetime will depend on ...
What is the role of the dilaton in Jackiw-Teitelboim 2D gravity?
2021年5月20日 · In a sense, this is the result of introducing a spacetime cutoff which moves the boundary inwards a bit. Because only at the boundary at spatial infinity gravity can be neglected, this cutoff boundary feels the effect of gravity and the dilaton becomes dynamical. This is often called the boundary particle.
Equations of motion of the metric in Classical Dilaton Gravity
2021年6月17日 · In these lecture notes by Strominger section 3.3 we derive the equations of motion of the Classical Dilaton Gravity action $$ S = \frac{1}{2\pi}\int{d^2x}{\sqrt{-g}e^{-2\phi}\left(R +4 (\nabla\phi)...
quantum field theory - Massive dilaton - Physics Stack Exchange
2018年6月16日 · Dilaton field is one of the matter fields which comes from the string theory. However, people consider it as a scalar field in black hole physics, so the dilaton particle in this regard is spinless. In the low energy limit, the mass of dilaton is zero and also it has no charge. So, all three quantum numbers of dilaton are zero.
Why is it ok to set the dilaton to its classical value in Jackiw ...
2023年4月17日 · The dilaton in JT gravity is a Lagrange multiplier, enforcing the constraint that the spacetime is AdS 2. You can then completely integrate out the dilaton, so you impose the constraint by hand and set the Lagrange multiplier to its classical value. That's also why the bulk term vanishes and you only get the boundary mode.
general relativity - Dilaton field causes apparent universe …
2021年10月30日 · Now I make the assumption that the apparent expansion of the universe is entirely due to the increase in the dilaton field $\phi(t)$ so that we have $$\phi(t)=a(t).\tag{8}$$ As $\phi(t)$ increases the masses of all particles increase and therefore their sizes decrease according to the uncertainty principle of quantum mechanics.
Einstein equations in 2 dimensional dilaton-gravity theories
2020年4月30日 · Doubts on the variation of the Einstein-Maxwell-Dilaton action Hot Network Questions Why is first faith and then believing mentioned with regard to overcoming the world in 1 John 5:4-5?