Your space questions, answered.
Every week, the readers of our space newsletter, The Airlock, send in their questions for space reporter Neel V. Patel to answer. This week: time dilation during space travel.
Elon Musk is one of the revolutionary figures in the world. Almost all of his ventures, such as SpaceX, Tesla and The Boring Company, are about making a difference in their own right. Musk has been a champion for all things alternative, whether it comes to cars or currency. However, he could trigger another great replacement.
From $10,000 per kg, possibly down to $15 per kg to orbit.
What it means for the future of humanity.
“Time-resolved photon-counting plays an indispensable role in precision metrology in both classical and quantum regimes. In particular, time-correlated single-photon counting (TCSPC) has been the key enabling technology for applications such as low-light fluorescence lifetime spectroscopy and photon counting time-of-flight (ToF) 3D imaging. However, state-of-the-art TCSPC single-photon timing resolution (SPTR) is limited in the range of 10–100 ps by the available single-photon detector technology. In this paper, we experimentally demonstrate a time-magnified TCSPC (TM-TCSPC) that achieves an unprecedentedly short SPTR of 550 fs for the first time with an off-the-shelf single-photon detector. The TM-TCSPC can resolve ultrashort pulses with a 130-fs pulsewidth difference at a 22-fs accuracy. When applied to photon counting ToF 3D imaging, the TM-TCSPC greatly suppresses the range walk error that limits all photon counting ToF 3D imaging systems by 99.2 % (130 times) and thus provides unprecedentedly high depth measurement accuracy and precision of 26 {\mu}m and 3 {\mu}m, respectively.”
The 1kW pico-hydro generation system can be used with factory drainage systems and irrigation canals. According to the manufacturer, it is made with 3D-printed sustainable materials based on recycled plastics and is able to generate electricity even with a small stream of water. Solar and storage may be linked to the system to ensure stable power supply.
It would take 15 billion years for the clock that occupies Jun Ye’s basement lab at the University of Colorado to lose a second—about how long the uni.
Using density functional theory calculations and the Greens’s function formalism, we report the existence of magnetic edge states with a non-collinear spin texture present on different edges of the 1T’ phase of the three monolayer transition metal dichalcogenides (TMDs): MoS$_2$, MoTe$_2$ and WTe$_2$. The magnetic states are gapless and accompanied by a spontaneous breaking of the time-reversal symmetry. This may have an impact on the prospects of utilizing WTe$_2$ as a quantum spin Hall insulator. It has previously been suggested that the topologically protected edge states of the 1T’ TMDs could be switched off by applying a perpendicular electric field. We confirm with fully self-consistent DFT calculations, that the topological edge states can be switched off. The investigated magnetic edge states are seen to be robust and remains gapless when applying a field.
Tesla CEO Elon Musk polled Twitter on Saturday, asking whether a new social media platform should be created to challenge Twitter and sparking speculation that the billionaire might be the one to do so.
In a series of tweets on Friday, the Space X founder asked if the time has come for a new platform to replace Twitter, and whether users thought the company ‘adhered to free speech principles.’
He said that, because Twitter serves as ‘the de factor public town square,’ a failure to promote free speech on the app would undermine democracy.
Physicists at the University of Sussex have discovered that black holes exert a pressure on their environment, in a scientific first.
In 1974 Stephen Hawking made the seminal discovery that black holes emit thermal radiation. Previous to that, black holes were believed to be inert, the final stages of a dying heavy star.
The University of Sussex scientists have shown that they are in fact even more complex thermodynamic systems, with not only a temperature but also a pressure.
The prospects for directly testing a theory of quantum gravity are poor, to put it mildly. To probe the ultra-tiny Planck scale, where quantum gravitational effects appear, you would need a particle accelerator as big as the Milky Way galaxy. Likewise, black holes hold singularities that are governed by quantum gravity, but no black holes are particularly close by — and even if they were, we could never hope to see what’s inside. Quantum gravity was also at work in the first moments of the Big Bang, but direct signals from that era are long gone, leaving us to decipher subtle clues that first appeared hundreds of thousands of years later.
But in a small lab just outside Palo Alto, the Stanford University professor Monika Schleier-Smith and her team are trying a different way to test quantum gravity, without black holes or galaxy-size particle accelerators. Physicists have been suggesting for over a decade that gravity — and even space-time itself — may emerge from a strange quantum connection called entanglement. Schleier-Smith and her collaborators are reverse-engineering the process. By engineering highly entangled quantum systems in a tabletop experiment, Schleier-Smith hopes to produce something that looks and acts like the warped space-time predicted by Albert Einstein’s theory of general relativity.
I have read about how you refuel an electric car is different. You don’t want to power an electric car on a power grid that uses fossil fuel. The goal is to have fully green refueling. I have theorized many things from my posts, such as using solar or wind with hydrogen storage. Also the components used to make batteries have an impact on the environment, unless I am wrong, as I can be wrong. I guess what I read must be wrong and Facebooks independent fact checkers are right. They always are right, and we must follow them. So please do.
