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RIP Mygazines 20082008

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first_imgWe thank you for your patronage. If you are a publisher interested in understanding more about our model and vision for the future of the publishing industry going forward, or to discuss our Business to Business model opportunities, please email us at mygazines@gmail.com. Sincerely,The Mygazines Team It’s over:Dear valued members, visitors and publishers, Due to monetary reasons and the state of the global economy, we unfortunately must close mygazines.com. We simply ran out of funds to support the daily operations. last_img

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Lighting Motorcycles Strike has struck but is it the bike we wanted

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first_img 0 Lightning Motorcycles’ Strike is getting us all charged up 2020 GMC Sierra HD first drive: Towing tech marvel More From Roadshow 8 Photos Share your voice 2020 BMW M340i review: A dash of M makes everything bettercenter_img 2019 Ford F-150 review: Popular pickup keeps on truckin’ Motorcycles Electric Cars Post a comment Enlarge ImageLightning’s Strike electric motorcycle packs 180 pound-feet of torque into a slightly more relaxed sportbike-like chassis. Lightning Motorcycle After months of teasing, the Lightning Motorcycles’ Strike is making its debut, and it looks promising, if not all that we hoped it would be.The base model Strike still comes in at the $13,000 price point that Lightning has been teasing, but its 70-to-100 mile range at that price point leaves something to be desired. That being said, the base model’s 10-kilowatt-hour battery can still be Level 2 charged in around two hours. If you want DC fast-charge capability on anything but the top-tier model, that will cost you an additional $1,500.The base Lightning’s performance — range notwithstanding — should be pretty decent though, with 90 horsepower on tap and a full 180 pound-feet of torque available at zero RPM. Stepping up to the top-of-the-line 20kWh model gets you an additional 30 horsepower. The base model bike weighs 455 pounds, while the Carbon Strike tips the scales at 485 pounds.Details on the suspension and brake components for the two lower-power models are a little scarce, but if you shell out nearly 20 large for the Carbon Strike edition, your bike will come with brakes by Brembo and suspension by Öhlins. You’ll also get an AIM dash with lap-timing abilities, and you’ll get your bike as early as July.Previous press releases from Lightning left us with a few questions about where the bike would be manufactured, since $13,000 is a relatively low price point for an electric motorcycle. Well, it happens that the answer isn’t as straightforward as “Made in America.” It’s more like “Made in America, sort of.”The bike undergoes final assembly at Lightning’s new facility in San Jose, California, but its components come from all over the world. Lightning isn’t giving us specifics on that, but it’s not uncommon for a vehicle’s various parts to come from many vendors around the world, and frankly, as long as the quality control from Lightning is good, we’re OK with that.So, in the end, was our excitement for the Strike justified? Kind of. Is it the world-beating, revolutionary, affordable electric motorcycle we were hoping for? At its entry-level price point, not really. The lack of standard DC fast charging across the range and the limited range of the base model aren’t ideal. The pricing structure that Lightning has going reminds us a lot of the one used by Zero.From a performance standpoint, we expect that the Strike will be a blast to ride. It’s not exactly a featherweight, but its combination of adequate power and stellar torque should be fun, and the slightly relaxed sportbike-like form factor should mean that it will do an excellent job of straightening out your favorite canyon road.The real test will come when we get to throw a leg over it. Tagslast_img read more

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Physics team finds new constraints on how lumpy spacetime can be

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first_img Gamma Ray Delay May Be Sign of ‘New Physics’ This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. (PhysOrg.com) — Robert Nemiroff and his colleagues at Michigan Technological University will be discussing new constraints on the so-called lumpiness of space-time at this year’s meeting of the American Astronomical Society. Image credit: NASA/Sonoma State University/Aurore Simonnet Nemiroff, also known for his Astronomy Pick of the Day site, has been studying photons that have been traveling through space for several billion years following a γ-ray burst that was recorded back in 1989. Called GRB 090510A, the burst let loose high energy photons that have been traveling through space at the speed of light; two of them are of special interest to physicists because they are believed to have left the same place at exactly the same time, which would seem to make them arrive here at exactly the same time as well. But, they won’t, due to the lumpiness of space-time and the long distance they have traveled. In the abstract for the presentation, the authors suggest that because a high-energy time scale for the photons detected from the gamma-ray burst have been found, a new upper limit is in place on the dependence of energy on speed and light as it’s dispersed across the universe.Studies of high energy photons traveling through space have already shown there are differences in actual speeds recorded, though they are very, very small; seven parts in a billion trillion, according to a previous study done by researchers at Yale. Because of this and other studied phenomenon, various researchers have theorized that space-time isn’t actually continues as it appears, but is instead made up of very, very tiny elements that are almost unbelievably small, on the order of a 10-35 (the Planck length). In such theories, photons that have the highest amount of energy also have wavelengths that are near to the Planck length. This makes them more apt to intermingle with so-called “lumps” which slows them down. The amount of slowdown is obviously very tiny, but as the photons travel so far for so long, the effect is amplified.In their study, Nemiroff et al, find due to measured differences in the arrival time of the two photons, that new constraints are in effect that impact the lump size of space-time. Because of this, the lumpiness of space-time only becomes meaningful when things are roughly 1/500 the Planck length, which could, obviously, put some limits on quantum gravity theories. More information: Nemiroff, R. J., Connolly, R., & Holmes, J. A New Limit on Lorentz Invariance and Chromatic Dispersion Across the Universe from GRB 090510A (American Astronomical Society, 2011)AbstractA high-energy, fast-variability time scale for Fermi-detected gamma-ray burst GRB 090510A is found that creates a new strictest upper limit on the energy dependence of the speed and dispersion of light across the universe. In particular, evidence is presented for variability at or below Δ t = 0.00136 for super-GeV photons, a factor of 10 more limiting than any time scale previously claimed for a GRB at GeV energies, including a previous limit reported by Abdo et al (2008). This variability derives from the duration of three separate closely-arriving photon groups prominent only in photon data above 1 GeV. One pulse pair has an energy difference of Δ E >/~ 23.5 GeV. Coupled with a redshift of z >/~ 0.897, the resulting limits on the differential speed of light and Lorentz invariance were found for a concordance cosmology. It was found that Δ c / c < 6.09 x 10-21, a limit consistent with, but slightly stronger than, a previous limit found for a GRB by Schaefer in 1999. Given a generic dispersion relation across the universe where the time delay is proportional to the photon energy to the first power, the variability translates into a dispersion strength of k1 < 1.38 x 10-5 sec Gpc-1 GeV-1. This limit results in an upper bound on dispersive effects created, for example, by dark energy, dark matter, or the spacetime foam of quantum gravity. This dispersion constraint also results in the most stringent lower limit yet claimed for the onset energy scale of quantum gravity: MQG c2 > 7.43 x 1021 GeV.via Nature Explore further Citation: Physics team finds new constraints on how lumpy space-time can be (2012, January 11) retrieved 18 August 2019 from https://phys.org/news/2012-01-physics-team-constraints-lumpy-space-time.html © 2011 PhysOrg.comlast_img read more

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Mysterious sharp symmetric features detected around young double star

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first_img This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Explore further Planetary influences on young stellar disks (Phys.org)—An international team of astronomers, led by Markus Janson of Stockholm University in Sweden, has discovered mysterious sharp symmetric features around young double star, named AK Sco. The discovery is baffling scientists as they are still unsure about the nature of these features, pondering the possibilities that they are highly eccentric rings or two separate spiral arms in the disk around the star. Moreover, these features may have been caused by circumbinary planets interacting with the disk. The results were published on Dec. 14 in the arXiv journal. AK Sco, located about 460 light years from Earth, is a spectroscopic binary star in the Upper Centaurus–Lupus (UCL) stellar association. It is a relatively young system, at least in astronomical terms, as scientists estimate it to be from 10 to 20 million years old. Spectroscopic binaries are systems in which the stars are so close together that they appear as a single star even in a telescope. The only evidence of a binary star comes from the Doppler effect on its emitted light. Periodic Doppler shifts of the wavelengths of lines are seen in the spectrum, as the stars move through their orbits.Janson and his colleagues made the discovery using the European Southern Observatory’s (ESO) Very Large Telescope (VLT), located in Chile. The observations were conducted in April 2015 as a part of the Search for Planets Orbiting Two Stars (SPOTS) program. The scientists made use of the Spectro-Polarimetric High-contrast Exoplanet Research (SPHERE) instrument recently installed on VLT. SPHERE is a powerful planet finder and its objective is to detect and study new giant exoplanets orbiting nearby stars using a method known as direct imaging.Detecting the sharp features in near-infrared imaging of AK Sco’s disk was a surprise for the scientists as they expected to find rather exoplanets in the neighborhood. However, what they found, might not be planets at all.”We report the discovery of resolved scattered light emission from the circumbinary disk around the well-studied young double star AK Sco. The sharp morphology of the imaged feature is surprising, given the smooth appearance of the disk in its spectral energy distribution,” the astronomers wrote in the paper.They researchers have noticed that the central binary star has a semi-major axis of approximately 0.16 astronomical units or AU and that the disk appears to have a gap with an inner rim at 0.58 AU. The images of AK Sco obtained by the SPHERE instrument reveal that the system has ‘arms’ extending from each side of the central star almost symmetrically. The scientists also found out that these features constitute scattered radiation from off-axis material in the circumbinary disk.The mysterious sharp features could represent an eccentric ring of material surrounding a gap. The scientists note that such structures are often found in disks that contain rings of material with gaps inside them. However, other observations conducted by ESO’s Atacama Large Millimeter Array (ALMA) don’t support this theory.Another explanation taken into account by Janson and his colleagues is that these structures are spiral arms that could be induced through gravitational instability or through the influence of a planet or binary companion. These two spiral arms are wound in opposite directions—one unwinding clockwise and the other counter-clockwise. But the fact that the features are so apparently symmetric, speaks against this hypothesis.What is worth noticing, either of these scenarios mentioned earlier, may point to circumbinary exoplanets in the disk. The features could be created by one or several planets interacting with the disk.Whichever proposed theory is true, the authors of the paper highlight the importance of the new generation adaptive optics systems – like this installed on the SPHERE instrument – in the search of disks around stars. They hope that these features will detected more often in near future as a result of implementing new technology of observations. SPHERE high-contrast images of AK Sco. All images show the two arms of the disk discussed in the paper. Credit: Markus Janson et al. 2015 © 2015 Phys.org More information: Detection of Sharp Symmetric Features in the Circumbinary Disk Around AK Sco, arXiv:1512.04552 [astro-ph.SR] arxiv.org/abs/1512.04552AbstractThe Search for Planets Orbiting Two Stars (SPOTS) survey aims to study the formation and distribution of planets in binary systems by detecting and characterizing circumbinary planets and their formation environments through direct imaging. With the SPHERE Extreme Adaptive Optics instrument, a good contrast can be achieved even at small (<300 mas) separations from bright stars, which enables studies of planets and disks in a separation range that was previously inaccessible. Here, we report the discovery of resolved scattered light emission from the circumbinary disk around the well-studied young double star AK Sco, at projected separations in the ~13—40 AU range. The sharp morphology of the imaged feature is surprising, given the smooth appearance of the disk in its spectral energy distribution. We show that the observed morphology can be represented either as a highly eccentric ring around AK Sco, or as two separate spiral arms in the disk, wound in opposite directions. The relative merits of these interpretations are discussed, as well as whether these features may have been caused by one or several circumbinary planets interacting with the disk. Citation: Mysterious sharp symmetric features detected around young double star (2015, December 17) retrieved 18 August 2019 from https://phys.org/news/2015-12-mysterious-sharp-symmetric-features-young.htmllast_img read more

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