Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

The Principle of Superposition and the Gravitational Field

The Principle of Superposition and the Gravitational Field

The principle of superposition applies to gravitational forces of objects that are sufficiently far apart. It states that the net gravitational force on a point object is the vector sum of the gravitational forces on it due to various objects. The principle helps calculate the force by listing the individual forces and then vectorially summing them up. However, it should be noted that the principle of superposition is not always apparent. In the presence of a second force, the first force could...

Detection of Black Holes

Detection of Black Holes

Although black holes were theoretically postulated in the 1920s, they remained outside the domain of observational astronomy until the 1970s.
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...

Principle of Equivalence

Principle of Equivalence

According to Albert Einstein (1897-1955), free-falling and feeling weightless are intrinsically linked. If a person were in free-fall under gravity, for example, diving towards the Earth from an airplane, they would feel completely weightless. Similarly, a person descending in a lift may feel partially weightless. Broadly speaking, it is assumed that an object in a uniform gravitational field and an object undergoing constant acceleration in the absence of gravity are under the same...

Space-Time Curvature and the General Theory of Relativity

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,...

Gravitation

Gravitation

In the years before Newton, a general belief prevailed that different laws governed objects in the sky than objects on Earth. When Kepler wrote down the three laws of planetary motion, explaining in detail the geometrical properties of the planetary orbits around the Sun, there was no immediate idea to discern their connection with more fundamental laws. It was Isaac Newton who, in 1665–66, figured out the connection between planetary motion, the motion of the moon around the Earth, and the...

Atomic Nuclei: Larmor Precession Frequency

Atomic Nuclei: Larmor Precession Frequency

The earth's gravitational field produces a 'twisting force' perpendicular to the angular momentum of a spinning mass (such as a spinning top) that causes the mass to 'wobble' around the gravitational field axis in a phenomenon called precession. Similarly, the magnetic moment (μ) of a spinning nucleus precesses due to an external magnetic field directed along the z-axis. The precession of the magnetic moment vector about the magnetic field is called Larmor precession, and the angular frequency...

You might also read

Related Articles

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

Sort by

Same author

Visualization of the influence of sodium citrate on iron and uranium precipitation in a 2D laboratory scale tank.

Journal of contaminant hydrology·2026

Same author

Correction to "Halloysite/polyaniline Nanocomposites for Enhanced Actinide Sorption".

ACS applied materials & interfaces·2026

Same author

Multiple Sources of Riparian Wetland Suspended Solids during Episodic Rain Events: Influence on Uranium Transport.

Environmental science & technology·2025

Same author

Halloysite/polyaniline Nanocomposites for Enhanced Actinide Sorption.

ACS applied materials & interfaces·2025

Same author

Comparison of measurement techniques and sorption of radium-226 in low and high salinity aqueous samples.

Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine·2025

Same author

Effect of seasonal anoxia on geochemical cycling in a stratified pond: Comparison to cooler pond conditions 40 years ago.

The Science of the total environment·2025

Search research articles

Related Experiment Video

Updated: Jun 1, 2026

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

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

Published on: August 12, 2013

Identifying the inflaton with primordial gravitational waves.

Damien A Easson¹, Brian A Powell

¹Department of Physics & School of Earth and Space Exploration & Beyond Center, Arizona State University, Tempe, Arizona 85287-1504, USA. easson@asu.edu

Physical Review Letters

|June 15, 2011

Summary

Experimental physics can reveal the gravitational Lagrangian of inflation. Precision measurements of primordial gravitational waves, specifically the tensor spectral index, can significantly reduce uncertainties in inflaton potentials, even without complex observables.

More Related Videos

Setting Limits on Supersymmetry Using Simplified Models

Setting Limits on Supersymmetry Using Simplified Models

Published on: November 15, 2013

Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing

Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing

Published on: March 22, 2019

Related Experiment Videos

Last Updated: Jun 1, 2026

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

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

Published on: August 12, 2013

Setting Limits on Supersymmetry Using Simplified Models

Setting Limits on Supersymmetry Using Simplified Models

Published on: November 15, 2013

Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing

Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing

Published on: March 22, 2019

Area of Science:

Cosmology
Theoretical Physics
Experimental Physics

Background:

Inflationary cosmology describes the early universe's rapid expansion.
The gravitational Lagrangian governs the dynamics of inflation.
Current observations have large degeneracies in inflationary parameters.

Purpose of the Study:

To investigate how experimental physics can constrain the inflationary gravitational Lagrangian.
To determine if future observables can reduce parameter space degeneracy.
To assess the impact of precision measurements on inflaton potential determination.

Main Methods:

Analyzing the relationship between observables and the inflationary Lagrangian.
Exploring the potential of future cosmological measurements (e.g., non-gaussianity, isocurvature modes).
Investigating the impact of precise tensor spectral index measurements from primordial gravitational waves.

Main Results:

Observable degeneracy in inflationary models is substantial.
Future observables like non-gaussianity and isocurvature modes may reduce degeneracy.
Precision measurement of the tensor spectral index can significantly constrain inflaton potentials, even without other advanced observables.

Conclusions:

Experimental physics plays a crucial role in uncovering the inflationary gravitational Lagrangian.
Direct detection of primordial gravitational waves and precise measurement of the tensor spectral index offer a powerful path to understanding inflation.
Reducing parameter space degeneracy is achievable through targeted future observations.