relativity

I would like to explain to someone about why the Sun's gravity does not pull the Earth into the Sun. I know that the reason that the Sun's gravity does not pull the Earth into the Sun is that the momentum of the Earth orbiting the Sun is in equilibrium with the Sun's gravity. What I need to... Read more

I solved gravity After deconstructing the complexities of general relativity and tensor calculus, I have developed a single, unified F= equation that accurately calculates gravitational force across all environments from gravitational orbits to Mercury's precession, and super massive... Read more

Einstein’s famous equation has grown into one of the great symbols of the 20th century. It is the one equation in science that people recognize, if any is. It has a kind of iconic status and dual connotations: the brilliance and insight of Einstein and the darkness of atomic bombs. Images. The basic idea behind […]

New claims challenge inconsistencies in one of the foundational principles of physics.

New research says time only exists where space is curved enough to support it, implying that our expanding universe is slowly losing its grip on time itself.

A humble elevator shaft was recently used in a test of the constancy of the speed of light. Credit: Jason Wong/Flickr , CC BY-NC-ND 2.0

Extremely curved spacetime can warp cause and effect, creating channels for backward communication

A new mathematical breakthrough sheds light on how tiny black holes could emerge from critical states of spacetime. Black holes are often portrayed as cosmic giants, swallowing stars and shaping entire galaxies. But some of the most intriguing black holes predicted by physics could be far smaller than an atom. For decades, scientists have known [...]

Antonio Leon wrote two brief arguments regarding the reality of centrifugal forces: the first based on Newton's Third Law of Mechanics, and the second on the Law of Dimensional Ho-mogeneity. He suggests that either centrifugal forces are real, or both the Law of Action and Reaction and the Law... Read more

physics, mathematical physics, philosophy of physics theory (physics), model (physics) experiment, measurement, computable physics Axiomatizations Tools Structural phenomena Types of quantum field thories examples The Lorentz force is the force exerted on a particle that is charged under the electromagnetic field. See relativistic particle for details. If one models the electromagnetic field via …

Black holes are among the most conceptually demanding structures of general relativity. This paper does not contest their physical description, does not modify general relativity, and does not propose a new theory of gravity. It offers an ontological reframing of the event horizon within Transformative Semalgebraic Ontology (OTS), understood here as a philosophical framework for distinguishing do…

Using just a pen and paper, a team of scientists has calculated how space and time could crystallize to form tiny black holes.

Maxwell's equations for electromagnetism break down as soon as charge is not conserved because the equations, by their very construction, operate under the requirement of conservation of charge. To ...

I'd like to share an observation and ask if others find it compelling. Consider a current-carrying loop that tends to expand. This is usually explained by the Lorentz force (IL×B) on each segment due to the field of the other segments. Equivalently, one can describe it in terms of the... Read more

I encountered this question and could not understand it: An observer on earth discovers that a spaceship heading east at $0.6c$ and a comet heading west at $0.8c$ will collide in $5$ seconds. From ...

The standard explanation of the Foucault pendulum is purely kinematic: the plane of oscillation stays fixed in inertial space while the planet rotates beneath it. But Norman Phillips (2000, 2001) showed that real forces — the horizontal component of Newtonian gravitation and centrifugal... Read more

My (very) rough sketch of the set up of the time-like singularity theorems as presented by Wald: 1. Get Raychaduri eqns and find that caustics form within finite proper time (given SEC and initially negative expansion). 2. Find conjugate points corresponding to those caustics between points in... Read more

Assistant Professor Haocun Yu is something of a scientific diplomat. In a recent Physical Review Letters (PRL) publication, she and colleagues show how a tabletop experiment can bring together two bedrock physics theories that have never been fully reconciled. Subatomic Gravity? More than a century ago Albert Einstein gave us the theory of general relativity, describing gravity […] The post Recon…

So far as I know in all of classical physics the reason we can avoid going into manifolds territory is that all calculations (integrals, coordinates, calculus, etc.) happen in at most one chart (and ...

By taking general relativity into higher dimensions, a trio of physicists has proven that a mathematical pattern of ripples in space-time geometry could give rise to naked singularities and microscopic black holes.