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Theoretical physicist known for his work on quantum gravity. He has worked at the Università la Sapienza of Rome, Imperial College London, the University of Pittsburgh and Yale University in the United States. He is a Full Professor at the Aix-Marseille Université in the Centre de Physique, Senior Member of the Institut Universitaire de France, the International Academy of Philosophy of Science, and Honorary Professor at Beijing Normal University. He has dedicated particular attention to the philosophy and history of ancient science and has recently completed a book on the Greek philosopher Anaximander “What is Science?” Mondadori 2011. He collaborates with the Sole 24 Ore and La Repubblica. (www.cpt.univ-mrs.fr/) In the spirit of ideas worth spreading, TEDx is a program of local, self-organized events that bring people together to share a TED-like experience. At a TEDx event, TEDTalks video and live speakers combine to spark deep discussion and connection in a small group. These local, self-organized events are branded TEDx, where x = independently organized TED event. The TED Conference provides general guidance for the TEDx program, but individual TEDx events are self-organized.* (*Subject to certain rules and regulations)

Primordial black holes (PBHs)—hypothetical objects formed by the gravitational collapse of dense regions in the early Universe—have been invoked as dark-matter candidates. But for PBHs to constitute all dark matter, they’d have to be extremely light, possibly weighing less than small asteroids. Now Elba Alonso-Monsalve and David Kaiser of the Massachusetts Institute of Technology show that these diminutive PBHs could possess an exotic property—a net color charge (such a charge characterizes quarks and gluons in quantum chromodynamics theory) [1]. Such color-charged PBHs might have left potentially observable signatures, says Kaiser.

Observations rule out that stellar-mass PBHs could fully explain dark matter, but PBHs weighing between 1017 and 1022 g remain viable candidates. Since a PBH’s mass should relate to its age, this mass range corresponds to PBH formation immediately after the big bang, when the Universe was still a hot plasma of unconfined quarks and gluons. Most PBHs would have formed by engulfing large numbers of quarks and gluons having a distribution of color charges. These PBHs would be color-charge neutral and sufficiently massive to live until today. However, the duo’s calculations show that a few PBHs could have formed from regions so tiny that the charges of the absorbed gluons would be correlated, giving these PBHs a net charge.

Color-charged black holes have long been considered to be mathematically possible, but the new study is the first to propose a realistic formation mechanism, says Kaiser. The small sizes imply that they would have since evaporated. Yet their presence in the early Universe might have disrupted the distribution of protons and neutrons when the big bang created the first nuclear isotopes, leaving subtle traces in the cosmic abundance of the elements.

When element 61, also known as promethium, was first isolated by scientists at the Department of Energy’s Oak Ridge National Laboratory in 1945, it completed the series of chemical elements known as lanthanides. However, aspects of the element’s exact chemical nature have remained a mystery until last year, when a team of scientists from ORNL and the National Institute of Standards and Technology used a combination of experimentation and computer simulation to purify the promethium radionuclide and synthesize a coordination complex that was characterized for the first time. The results of their work were recently published in Nature.

Stephen Paul KIng [always] has [good] ideas—especially for [error] rectification.


Fay Dowker is a physicist and is currently a professor of Theoretical Physics and a member of the Theoretical Physics Group at Imperial College London and a Visiting Fellow at the Perimeter Institute. Fay conducts research in a number of areas of theoretical physics including quantum gravity and causal set theory.

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A simple concept of decay and fission of “magnetic quivers” helps to clarify complex quantum physics and mathematical structures.

Researchers employed magnetic quivers to delve into the fundamentals of quantum physics, specifically through the lens of supersymmetric quantum field theories. They have provided a novel interpretation of the Higgs mechanism, illustrating how particles gain mass and the potential decay and fission within QFTs.

Pioneering Quantum Physics Study

The American theoretical physicist, Brian Greene explains various hypotheses about the causation of the big bang. Brian Greene is an excellent science communicator and he makes complex cosmological concepts more easy to understand.

The Big Bang explains the evolution of the universe from a starting density and temperature that is currently well beyond humanity’s capability to replicate. Thus the most extreme conditions and earliest times of the universe are speculative and any explanation for what caused the big bang should be taken with a grain of salt. Nevertheless that shouldn’t stop us to ask questions like what was there before the big bang.

Brian Greene mentions the possibility that time itself may have originated with the birth of the cosmos about 13.8 billion years ago.

To understand how the Universe came to be, scientists combine mathematical models with observations and develop workable theories which explain the evolution of the cosmos. The Big Bang theory, which is built upon the equations of classical general relativity, indicates a singularity at the origin of cosmic time.

However, the physical theories of general relativity and quantum mechanics as currently realized are not applicable before the Planck epoch, which is the earliest period of time in the history of the universe, and correcting this will require the development of a correct treatment of quantum gravity.

Certain quantum gravity treatments imply that time itself could be an emergent property. Which leads some physicists to conclude that time did not exist before the Big Bang. While others are open to the possibility of time preceding the big bang.