What curvature will the universe have if the matter and energy density of the universe is equal to the critical density? Open Closed Flat None of the above

Q: About how much of the universe is believed to be composed of dark energy? O 68-73% O 10-12% O 4-5% O…

A: We know very less about the universe . and said universe is expand .  the maximum thing is unknown…

Q: Which Feynman diagram could show an electron emitting a photon. ?

A:

Q: Mp = 1 and Mpl is the planks mass (reduced). %3D Assuming natural units where 8rG

A: efrrfgnourfnourfouroqunfouqoefrrfgnourfnourfouroqunfouqoefrrfgnourfnourfouroqunfouqoefrrfgnourfnourf…

Q: Estimate the mass contained in the Milky Way galaxy blackhole.

A: Schwarzschild radius also known as the gravitational radius is the limit to which an object can…

Q: The nuclei of some galaxics are thought to contain supermassive black holes with M = 3 x 10°M9. How…

A: The Schwarzschild radius of a supermassive black hole can be estimated using an empirical…

Q: Investigate the concept of duality in string theory and its implications for understanding the…

A: Duality is a fundamental concept in string theory that has profound implications for our…

Q: What is the role of symmetry in fundamental physics? Provide examples of symmetry principles in…

A: Symmetry plays a fundamental role in physics as it helps to simplify complex problems and provides a…

Q: Find the order of this Feynman diagram

A: Given:

Q: Critical density of a universe is found to be 6×10-27 kg/m. Estimate the value of Hubble constant.

A: It was observed that galaxies are moving away from each other and the farther they are faster they…

Q: 40 Because the apparent recessional speeds of galaxies and quasars at great distances are close to…

A:

Q: diation density and m

A: The conditions and the assumptions as,

Q: The critical mass density needed to just halt the expansion of the universe is approximately 10-26…

A: Given that,The critical mass density = 10-26 kg/m3Average mass = 7 eV/c2As we know that,If m is in…

Q: 3. Suppose the scale factor varies as a(t) = Act, where A and a are constants. (a) Can the constant…

A: Given, The scale factor varies as at=Aeαt

Q: What is the significance of the Boltzmann distribution?

A:

Q: Show that in matter dominated universe density behave as p x (1+z)3 , in radiation dominated as px…

A:

Q: Explain why the cosmological principle requires that H0 must have the same value everywhere in…

A: Given Explain why the cosmological principle requires that H0 must have the same value everywhere in…

Q: Describe the Feynman diagram for the exchange of a between a proton and a neutron.

A: When a proton decays into a neutron then an exchange particle is W+ And the other products are…

Q: When a distant galaxy is observed the violet hydrogen line of 410.173 nm was recorded at 610 nm.…

A: When it comes to light the Doppler effect has to be modified. Light does not require any medium to…

Q: What was the age of the Universe when the redshift was 3,000? Assume the Cosmological Constant is…

A: Given the redshift z = 3000. Take Hubble's constant…

Q: Define the term  Boltzmann constant?

A: The expression of Boltzmann constant is: kB=R/NA     ……….(1) Here, kB is the Boltzmann constant, R…

Q: Time period of rotation of a blackhole is 5.52 milliseconds. What is the frequency of rotation in SI…

A: Given data: Time period of rotation of a blackhole is, T=5.52 ms=5.52×10-3 s.

Q: Is it possible that Nothing can Exist, as in a vacuum? If so, what holds the matter of the universe…

A: According to present-day understanding of what is called the vacuum state or the quantum vacuum, it…

Q: b) a) W+ d dr dg UR UB d) ERG c) ūR UG UR

A:

Q: Estimate the critical density of the universe if the Hubble's constant was 100 km/s/Mpc.

A:

Q: Albert Einstein's original field equation would have been able to theoretically have predicted the…

A: Albert Einstein, in 1916 published his great theory of General Relativity which described gravity as…

Q: Hubble law describes how the speed of recession of distant galaxies varies with the distance from…

A: Introduction: Hubble law: It is used for describing the age of the universe since the big bang. It…

Q: If the universe had a density equal to the critical density (a flat universe) and the Hubble…

A: Everything is contained within the universe. It includes all of the space as well as all of the…

Q: Estimate the critical density of the universe if the Hubble's constant was 50 km/s/Mpc.

A: The minimum density that is required to stop the expansion of the universe is defined as the…

Q: If the universe is infinite, does it have a center? Discuss.

A: The universe is infinite, and what is know about the universe is gathered by analysing the…

Q: Assume that the universe has an edge. Placing yourself at that edge in a thought experiment, explain…

A: Given Assume that the universe has an edge. Placing yourself at that edge in a thought experiment,…

Q: Show that in matter dominated universe density behave as p c (1+z) , in radiation dominated as px…

A:

Q: The CMB decoupled at redshift z≈ 1100, i.e., when its frequency was a factor of z larger. The…

A: The CMB or common microwave background is composed of photons. It is the leftover radiation amount…

Q: If some unknown cause of red shift—such as light becoming “tired” from traveling long distances…

A:

Q: 46 Figure 44-12 is a hypothetical plot of the recessional speeds v of galaxies against their…

A:

Q: 1. Assuming a spatially flat Universe, find the time dependence of: (a) the density of matter when…

A:

Q: his a question on Cosmology: Suppose that you have a flat universe that has matter and dark energy…

A: The value of matter energy density parameter at present day is  Ωm,0=1-Ωd,0 Substitute the value of…

Stellar evolution

We may see thousands of stars in the dark sky. Our universe consists of billions of stars. Stars may appear tiny to us but they are huge balls of gasses. Sun is a star of average size. Some stars are even a thousand times larger than the sun. The stars do not exist forever they have a certain lifetime. The life span of the sun is about 10 billion years. The star undergoes various changes during its lifetime, this process is called stellar evolution. The structure of the sun-like star is shown below.

Red Shift

It is an astronomical phenomenon. In this phenomenon, increase in wavelength with corresponding decrease in photon energy and frequency of radiation of light. It is the displacement of spectrum of any kind of astronomical object to the longer wavelengths (red) side.