theoretical physics – Quanta Magazine

Diminishing Dark Energy May Evade the ‘Swampland’ of Impossible Universes

Steve Nadis — Mon, 19 Aug 2024 14:20:11 +0000

On the morning of April 4, physicists filed into a third-floor meeting room at Harvard University’s Jefferson Laboratory. Word had gotten out that there would be a big announcement from the Dark Energy Spectroscopic Instrument (DESI) collaboration, a group of physicists who are investigating dark energy — a mysterious, repulsive form of energy that permeates the universe. The meeting room at...

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‘Metaphysical Experiments’ Probe Our Hidden Assumptions About Reality

Amanda Gefter — Tue, 30 Jul 2024 14:40:10 +0000

Metaphysics is the branch of philosophy that deals in the deep scaffolding of the world: the nature of space, time, causation and existence, the foundations of reality itself. It’s generally considered untestable, since metaphysical assumptions underlie all our efforts to conduct tests and interpret results. Those assumptions usually go unspoken. Most of the time, that’s fine.

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Vacuum of Space to Decay Sooner Than Expected (but Still Not Soon)

Matt von Hippel — Mon, 22 Jul 2024 13:45:36 +0000

Vacuum decay, a process that could end the universe as we know it, may happen 10,000 times sooner than expected. Fortunately, it still won’t happen for a very, very long time. When physicists speak of “the vacuum,” the term sounds as though it refers to empty space, and in a sense it does. More specifically, it refers to a set of defaults, like settings on a control board. When the quantum fields...

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Dogged Dark Matter Hunters Find New Hiding Places to Check

Lyndie Chiou — Tue, 07 May 2024 14:37:01 +0000

The end is brutal for electrons hurtling at 99.9999999% of the speed of light through SLAC National Accelerator Laboratory’s two-mile-long beam pipe: a final slam into End Station A. In the late 1960s and early ’70s, such collisions broke apart protons and neutrons to reveal the elementary particles that make them up. The discovery won the experiment’s leader a Nobel Prize. “End Station A is this...

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AI Starts to Sift Through String Theory’s Near-Endless Possibilities

Charlie Wood — Tue, 23 Apr 2024 14:00:56 +0000

String theory captured the hearts and minds of many physicists decades ago because of a beautiful simplicity. Zoom in far enough on a patch of space, the theory says, and you won’t see a menagerie of particles or jittery quantum fields. There will only be identical strands of energy, vibrating and merging and separating. By the late 1980s, physicists found that these “strings” can cavort in just a...

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