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# Quantum gravity

## Latest Articles

### Does Time Really Flow? New Clues Come From a Century-Old Approach to Math.

The laws of physics imply that the passage of time is an illusion. To avoid this conclusion, we might have to rethink the reality of infinitely precise numbers.

### Why the Laws of Physics Are Inevitable

By considering simple symmetries, physicists working on the “bootstrap” can rediscover the basic form of the known forces that shape the universe.

### Black Hole Singularities Are as Inescapable as Expected

For the first time, physicists have calculated exactly what kind of singularity lies at the center of a realistic black hole.

### The Simple Idea Behind Einstein’s Greatest Discoveries

Lurking behind Einstein’s theory of gravity and our modern understanding of particle physics is the deceptively simple idea of symmetry. But physicists are beginning to question whether focusing on symmetry is still as productive as it once was.

### Philosophers Debate New ‘Sonic Black Hole’ Discovery

Opinions differ about what recent measurements of a sound-trapping fluid reveal about light-trapping black holes.

### How Our Universe Could Emerge as a Hologram

Physicists have devised a holographic model of “de Sitter space,” the term for a universe like ours, that could give us new clues about the origin of space and time.

### The Double Life of Black Holes

Perfect black holes are versatile mathematical tools. Just don’t mistake them for the real thing.

### How Space and Time Could Be a Quantum Error-Correcting Code

The same codes needed to thwart errors in quantum computers may also give the fabric of space-time its intrinsic robustness.

### How Holography Could Help Solve Quantum Gravity

In the latest campaign to reconcile Einstein’s theory of gravity with quantum mechanics, many physicists are studying how a higher dimensional space that includes gravity arises like a hologram from a lower dimensional particle theory.