Miniature black hole
Since string theory is essentially the theory of the entire universe, to conduct direct testing it, a universe needs to be established in the laboratory. Generally, we expect the quantum effect of gravity to appear under Planck energy conditions,
is more powerful than our most powerful particle accelerator in the fourth power (quadrillion times), so it is impossible to conduct direct testing of string theory. However, if there is indeed an parallel universe less than 1 mm away from us,
then the energy required to make the unity and quantum effects appear may be quite low, and our next generation particle accelerator, such as Large Hadron Collider (LHC), has the ability to do it. This in turn triggered a craze for research on black hole physics, the most exciting of which is the "mini-black hole". Micro black holes are manifested like subatomic particles, which are a kind of "laboratory" in which some predictions in string theory can be tested. With the Large Hadron Collider (LHC) it is possible to create micro black holes, and physicists are excited about it. (Miniature black holes are as small as electrons, so they are not afraid of swallowing the entire earth. Generally, the cosmic rays that reach the earth have more energy than these micro black holes, but they do not have an adverse effect on the earth.)
black holes appear as subatomic particles. Although it sounds quite subversive, it is actually an idea that has been proposed by Einstein in 1935. In Einstein's view, there must be an unified field theory , in which matter composed of subatomic particles can be regarded as a distorted phenomenon in the space-time structure. In his opinion, subatomic particles like electrons are actually some "line pimples" or wormholes curled in space, they just look like particles at a certain distance. Einstein and Nathan Rosen were playing with the idea that electrons might actually be disguised micro black holes. In his way, he wanted to incorporate matter into this unified field theory, which would eventually degrade subatomic particles into pure geometry.
micro black hole was later proposed by Stephen Hawking. He proved that the black hole would definitely evaporate and emit a faint energy. The black hole continuously emits energy for billions of years, and gradually shrinks, and eventually becomes the size of a subatomic particle.
string theory has now introduced the concept of micro black holes again. Recall that a black hole is formed when a large amount of matter is compressed within its Schwarzsie radius . Since matter and energy can be converted to each other, black holes can also be created by compressing energy. People are looking forward to whether the Large Hadron Collider (LHC) can collide two protons and at the energy of 14 trillion electron volts to create micro black holes from the resulting fragments. These black holes will be very small, probably as heavy as 1,000 times the mass of an electron, and may last only 10 to 23 seconds. However, it is clearly distinguishable in the subatomic particle trajectory created by LHC.
Physicists also hope that cosmic rays in outer space may also contain micro black holes. Pierre Auger's Cosmic Ray Observatory, based in Argentina, is very sensitive and can detect several of the largest cosmic ray bursts recorded in scientific history. Since cosmic rays will produce obvious characteristics of radiation when they reach the high-level atmosphere of the Earth, people hope that micro black holes can be found naturally. A calculation shows that Auger's cosmic ray detector may discover 10 consmic rays showers emitted by micro black hole bows every year.
Maybe during this decade, the Large Hadron Collider (LHC) in Switzerland or the Auger cosmic ray detector in Argentina will detect micro black holes, which may provide good evidence for the existence of parallel universes. Although it may not be able to prove that string theory is correct once and for all, it can convince the entire physics community that string theory matches all experimental results and is in the right direction.
