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Simulation Argument (Planck Scale)
Programming deep universe (Programmer God) Simulation Hypothesis models at the Planck scale The simulation hypothesis or simulation argument is the argument that proposes all current existence, including the Earth and the rest of the universe, could be an artificial simulation, such as a computer simulation. The ancestor simulation approach, which Nick Bostrom called "the simulation argument", argues for "high-fidelity" simulations of ancestral life that would be indistinguishable from reality to the simulated ancestor. However this simulation variant can be traced back to an 'organic base reality' (the original programmer ancestors). The Programmer God approach conversely states that the universe simulation began with the big bang (the deep universe simulation) and was programmed by an external intelligence (external to the universe), the Programmer by definition a God in the creator of the universe context. As the universe in its entirety, down to the smallest detail, is within the simulation, coding will occur at the lowest level. In Big Bang cosmology, the Planck epoch or Planck era is the earliest stage of the Big Bang, where cosmic time was equal to Planck time. In analyzing the feasibility of a Programmer God simulation, Planck time therefore becomes the reference for the simulation clock-rate, with the simulation operating at or below the Planck scale, and with the Planck units as (top-level) candidates for the base (mass, length, time, charge) units.
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Topic Review
2020 AV2
2020 AV2 is a near-Earth asteroid discovered by the Zwicky Transient Facility on 4 January 2020. It is the first asteroid discovered to have an orbit completely within Venus's orbit, and is thus the first and only known member of the inner-Venusian Vatira population of Atira-class asteroids. 2020 AV2 has the smallest known aphelion and third-smallest known semi-major axis among all asteroids. With an absolute magnitude around 16.4, the asteroid is expected to be larger than 1 km in diameter.
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Topic Review
Shock Capturing Method
In computational fluid dynamics, shock-capturing methods are a class of techniques for computing inviscid flows with shock waves. The computation of flow containing shock waves is an extremely difficult task because such flows result in sharp, discontinuous changes in flow variables such as pressure, temperature, density, and velocity across the shock.
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Topic Review
Action
In physics, action is a numerical value describing how a physical system has changed over time. Action is significant because the equations of motion of the system can be derived through the principle of stationary action. In the simple case of a single particle moving with a specified velocity, the action is the momentum of the particle times the distance it moves, added up along its path, or equivalently, twice its kinetic energy times the length of time for which it has that amount of energy, added up over the period of time under consideration. For more complicated systems, all such quantities are added together. More formally, action is a mathematical functional which takes the trajectory, also called path or history, of the system as its argument and has a real number as its result. Generally, the action takes different values for different paths. Action has dimensions of energy × time or momentum × length, and its SI unit is joule-second (like the Planck constant h).
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Biography
Richard Garwin
Richard Lawrence Garwin (born April 19, 1928) is an United States physicist, widely known to be the author of the first hydrogen bomb design.[1][2] Garwin received his bachelor's degree from the Case Institute of Technology in 1947, and two years later his Ph.D. from the University of Chicago under the supervision of Enrico Fermi at the age of 21. Another of Fermi's students, Marvin L. Goldbe
  • 551
  • 25 Nov 2022
Topic Review
Mir EO-28
Soyuz TM-30 (Russian: Союз ТМ-30, Union TM-30), also known as Mir EO-28, was a Soyuz mission, the 39th and final human spaceflight to the Mir space station. The crew of the mission was sent by MirCorp, a privately funded company, to reactivate and repair the station. The crew also resupplied the station and boosted the station to an orbit with a low point (perigee) of 360 and a high point (apogee) of 378 kilometers (223 and 235 miles, respectively); the boost in the station's orbit was done by utilizing the engines of the Progress M1-1 and M1-2 spacecraft. At that time a transit between Mir and the International Space Station was already impossible - such a transfer was deemed undesired by NASA - and the orbital plane of ISS had been chosen some time before to be around 120 degrees away from that of Mir. The mission was the first privately funded mission to a space station. The mission was part of an effort by MirCorp to refurbish and privatize the aging Mir space station, which was nearing the end of its operational life. Further commercially funded missions beyond Soyuz TM-30 were originally planned to continue the restoration efforts of the then 14-year-old space station, but insufficient funding and investment ultimately led to the de-orbit of the station in early 2001.
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Biography
Prabhakar Misra
Prabhakar Misra is an American physicist, who researches and teaches at Howard University in Washington, D.C., and is currently a Professor in the Department of Physics and Astronomy. Born and raised in India, he came to the United States to pursue graduate studies in physics. He earned an M.S. in Physics from Carnegie Mellon University in 1981 (Pittsburgh, Pennsylvania), followed by a Ph D.
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Topic Review
Drinking Bird
Drinking birds, also known as insatiable birdies, dunking birds, drinky birds, water birds, dipping birds, and “Sippy Chickens” are toy heat engines that mimic the motions of a bird drinking from a water source. They are sometimes incorrectly considered examples of a perpetual motion device.
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  • 25 Nov 2022
Topic Review
RESOLFT
RESOLFT, an acronym for REversible Saturable OpticaL Fluorescence Transitions, denotes a group of optical fluorescence microscopy techniques with very high resolution. Using standard far field visible light optics a resolution far below the diffraction limit down to molecular scales can be obtained. With conventional microscopy techniques, it is not possible to distinguish features that are located at distances less than about half the wavelength used (i.e. about 200 nm for visible light). This diffraction limit is based on the wave nature of light. In conventional microscopes the limit is determined by the used wavelength and the numerical aperture of the optical system. The RESOLFT concept surmounts this limit by temporarily switching the molecules to a state in which they cannot send a (fluorescence-) signal upon illumination. This concept is different from for example electron microscopy where instead the used wavelength is much smaller.
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Topic Review
The Advanced Applications of 2D Materials in SERS
Surface-enhanced Raman scattering (SERS) as a label-free, non-contact, highly sensitive, and powerful technique has been widely applied in determining bio- and chemical molecules with fingerprint recognitions. 2-dimensional (2D) materials with layered structures, tunable optical properties, good chemical/physical stabilities, and strong charge–transfer interaction with molecules have attracted researchers’ interests. Two-D materials with a large and flat surface area, as well as good biocompatibility have been considered promising candidates in SERS and widely applied in chemical and bio-applications. It is well known that the noble metallic nanostructures with localized surface plasmon effects dominate the SERS performance. The combination of noble metallic nanostructure with 2D materials is becoming a new and attractive research domain. The SERS substrates combined with 2D materials, such as 2D graphene/metallic NPs, 2D materials@metallic core-shell structures, and metallic structure/2D materials/metallic structure are intensely studied.
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