Jove
Visualize
Contact Us

Related Concept Videos

Space-Time Curvature and the General Theory of Relativity01:17

Space-Time Curvature and the General Theory of Relativity

In 1905, Albert Einstein published his special theory of relativity. According to this theory, no matter in the universe can attain a speed greater than the speed of light in a vacuum, which thus serves as the speed limit of the universe.
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,...
Newtonian Fluid: Problem Solving01:18

Newtonian Fluid: Problem Solving

Newtonian fluids exhibit a constant viscosity, meaning their shear stress and shear strain rate are directly proportional. This property ensures a predictable and stable response to applied forces, maintaining a linear relationship between force and flow. Examples include water, air, and light oils, consistently demonstrating this proportional behavior regardless of external conditions.
A velocity gradient forms within the fluid when a Newtonian fluid is placed between two parallel plates, with...
Symmetry in Maxwell's Equations01:28

Symmetry in Maxwell's Equations

Once the fields have been calculated using Maxwell's four equations, the Lorentz force equation gives the force that the fields exert on a charged particle moving with a certain velocity. The Lorentz force equation combines the force of the electric field and of the magnetic field on the moving charge. Maxwell's equations and the Lorentz force law together encompass all the laws of electricity and magnetism. The symmetry that Maxwell introduced into his mathematical framework may not be...
Gauss's Law: Problem-Solving01:10

Gauss's Law: Problem-Solving

Gauss's law helps determine electric fields even though the law is not directly about electric fields but electric flux. In situations with certain symmetries (spherical, cylindrical, or planar) in the charge distribution, the electric field can be deduced based on the knowledge of the electric flux. In these systems, we can find a Gaussian surface S over which the electric field has a constant magnitude. Furthermore, suppose the electric field is parallel (or antiparallel) to the area vector...
Reduced Mass Coordinates: Isolated Two-body Problem01:12

Reduced Mass Coordinates: Isolated Two-body Problem

In classical mechanics, the two-body problem is one of the fundamental problems describing the motion of two interacting bodies under gravity or any other central force. When considering the motion of two bodies, one of the most important concepts is the reduced mass coordinates, a quantity that allows the two-body problem to be solved like a single-body problem. In these circumstances, it is assumed that a single body with reduced mass revolves around another body fixed in a position with an...
Maxwell-Boltzmann Distribution: Problem Solving01:20

Maxwell-Boltzmann Distribution: Problem Solving

Individual molecules in a gas move in random directions, but a gas containing numerous molecules has a predictable distribution of molecular speeds, which is known as the Maxwell-Boltzmann distribution, f(v).
This distribution function f(v) is defined by saying that the expected number N (v1,v2) of particles with speeds between v1 and v2 is given by

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Four direct measurements of the fine-structure constant 13 billion years ago.

Science advances·2020
Same author

The area of a rough black hole.

Physics letters. [Part B]·2020
Same author

Reconstructions of the dark-energy equation of state and the inflationary potential.

General relativity and gravitation·2019
Same author

Szekeres universes with homogeneous scalar fields.

The European physical journal. C, Particles and fields·2019
Same author

Limits on the dependence of the fine-structure constant on gravitational potential from white-dwarf spectra.

Physical review letters·2013
Same author

Active galactic nuclei shed light on axionlike particles.

Physical review letters·2009
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Video

Updated: Jun 3, 2026

Setting Limits on Supersymmetry Using Simplified Models
07:46

Setting Limits on Supersymmetry Using Simplified Models

Published on: November 15, 2013

New solution of the cosmological constant problems.

John D Barrow1, Douglas J Shaw

  • 1DAMTP, Centre for Mathematical Sciences, Cambridge CB3 0WA, United Kingdom.

Physical Review Letters
|April 8, 2011
PubMed
Summary

This study treats the cosmological constant as a field, yielding an integral constraint for its effective value. The research predicts the effective cosmological constant

Area of Science:

  • Cosmology
  • Gravitational Physics
  • Theoretical Physics

Background:

  • The cosmological constant (CC) problem is a major challenge in modern physics.
  • Current models often require fine-tuning or additional dark-energy fields to explain observed cosmic acceleration.
  • The standard gravitational action principle does not inherently explain the observed value of the CC.

Purpose of the Study:

  • To propose a new theoretical framework for the cosmological constant by treating it as a field.
  • To derive an integral constraint equation for the effective CC from gravitational action.
  • To provide a new perspective on the time evolution of the Universe and its properties.

Main Methods:

  • Extended the standard gravitational action principle by promoting the bare cosmological constant to a field.

More Related Videos

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
12:14

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry

Published on: August 12, 2013

Related Experiment Videos

Last Updated: Jun 3, 2026

Setting Limits on Supersymmetry Using Simplified Models
07:46

Setting Limits on Supersymmetry Using Simplified Models

Published on: November 15, 2013

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
12:14

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry

Published on: August 12, 2013

  • Performed variation to derive a new integral constraint equation.
  • Calculated the expected value of the effective CC from measurable quantities.

    • Main Results:

    • Derived an integral constraint equation for the classical value of the effective CC.
    • Calculated the expected value of the effective CC to be O(t(U)(-2)), consistent with observations.
    • Made a falsifiable prediction for the spatial curvature parameter: Ω(k0) = -0.0055.

    Conclusions:

    • The proposed model offers a new view of time evolution without requiring fine-tunings or extra dark-energy fields.
    • The framework naturally explains the observed magnitude of the effective CC.
    • The prediction for spatial curvature provides a testable avenue for future research.