Could vacuum physics be revealed by laser-driven microbubble?

A "vacuum" is generally thought to be nothing but empty space. But in fact, a vacuum is filled with "virtual particle-antiparticle pairs" of electrons and positrons that are continuously created and annihilated in unimaginably short time-scales.

The quest for a better understanding of vacuum physics will lead to the elucidation of fundamental questions in modern physics, which is integral in unravelling the mysteries of space exploration such as the Big Bang.

However, to forcibly separate the virtual pairs using a laser's electric field and cause them to appear not as virtual particles but real particles, the laser intensity required would be ten million times higher than what today's laser technology is capable of. This field intensity is the so-called "Schwinger limit", named a half century ago after the American Nobel laureate, Julian Schwinger.

Scientists at Osaka University discovered a novel mechanism which they refer to as microbubble implosion (MBI) in 2018. In MBI, super-high energy hydrogen ions (relativistic protons) are emitted at the moment when bubbles shrink to atomic size through the irradiation of hydrides with micron-sized spherical bubbles by ultraintense, ultrashort laser pulses.

In this study, the group led by Masakatsu Murakami confirmed that during MBI, an ultrahigh electrostatic field close to the Schwinger field could be achieved because micron-sized bubbles embedded in a solid hydride target implode to have nanometer-sized diameters upon ionization.

From the 3D simulations carried out at the Osaka University Institute of Laser Engineering, they also found that the density during the maximum compression of the bubble reaches several hundred thousand to one million times solid density.

At this density, something no larger than a lump sugar would weigh a few hundred kilograms. The energy density at the bubble center was found to be about one million times higher than that at the sun. These astonishing numbers have been thought to be impossible to achieve on Earth. Their research results were published in Physics of Plasmas.

Research paper

Related Links
Osaka University
Understanding Time and Space

Tweet

Thanks for being there;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Monthly Supporter
$5+ Billed Monthly

paypal only

SpaceDaily Contributor
$5 Billed Once

credit card or paypal

Theoretical physicists unveil one of the most ubiquitous and elusive concepts in chemistry
Trieste, Italy (SPX) Jul 02, 2019
Even if we study them at school, oxidation numbers have so far eluded any rigorous quantum mechanical definition. A new SISSA study, published in Nature Physics, reverses this state of affairs by providing such a definition, based on the theory of topological quantum numbers, which was honoured with the 2016 Nobel prize in Physics awarded to Thouless, Haldane and Kosterlitz. This result, combined with recent advances in the theory of transport achieved at SISSA, paves the way to an accurate, yet t ... read more