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The 2015 Planck data release tightened the region of the allowed inflationary models. Inflationary models with convex potentials have now been ruled out since they produce a large tensor to scalar ratio. Meanwhile the same data offers interesting hints on possible deviations from the standard picture of CMB perturbations. Here we revisit the predictions of the theory of the origin of the universe from the landscape multiverse for the case of exponential inflation, for two reasons: firstly to check the status of the anomalies associated with this theory, in the light of the recent Planck data; secondly, to search for a counterexample whereby new physics modifications may bring convex inflationary potentials, thought to have been ruled out, back into the region of potentials allowed by data. Using the exponential inflation as an example of convex potentials, we find that the answer to both tests is positive: modifications to the perturbation spectrum and to the Newtonian potential of the universe originating from the quantum entanglement, bring the exponential potential, back within the allowed region of current data; and, the series of anomalies previously predicted in this theory, is still in good agreement with current data. Hence our finding for this convex potential comes at the price of allowing for additional thermal relic particles, equivalently dark radiation, in the early universe.

Read this paper on arXiv…

E. Valentino and L. Mersini-Houghton Wed, 28 Dec 16 26/46.

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Creating tunable terahertz radiation.


Indium arsenide quantum dots in gallium arsenide wafers offer wider pump-wavelength range, significantly higher thermal tolerance, and higher conversion efficiency than typical terahertz radiation sources.

The terahertz (THz) range of electromagnetic waves (0.1–10THz)—which lies between the microwave and optical regions—is of great interest. This is mainly because this band of the electromagnetic spectrum includes the frequencies of rotational and vibrational spectra of complex (e.g., biological) molecules. Most dielectric materials are transparent in the THz region, and THz waves are already used in many biomedical applications (e.g., for the detection of dangerous and illicit substances, as well as for the diagnosis and treatment of diseases). Photoconductive antennas are the most-developed room-temperature sources of THz radiation. However, ultrafast low-temperature-grown gallium arsenide (GaAs)—which is typically used as a substrate for such antennas—suffers (because of its large band gap) from low thermal efficiency, low carrier mobility, and a pump limit at a wavelength of about 850nm.

(Photo courtesy of Clarius Mobile Health)

The ultrasound market currently stands as a $6 billion global industry.

Contrary to popular perception, the use of ultrasounds for women’s health and pregnancy follow-ups only represents less than 20% of the overall use for healthcare. For example, a diagnostic ultrasound is routinely used to diagnose an assortment of healthcare conditions such as cancer, gall stones, and cardiovascular diseases.

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The video of an accident on the Autobahn in the Netherlands caught on the dashcam of a Tesla Model X shows the Autopilot’s forward collision warning predicting an accident before it could be detected by the driver.

With the release of Tesla’s version 8.0 software update in September, the automaker announced a new radar processing technology that was directly pushed over-the-air to all its vehicles equipped with the first generation Autopilot hardware.

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Inspired by the comic book character Wolverine, scientists have developed a self-healing, highly stretchable, transparent material that can be used to power artificial muscles.

The end product is a soft, rubber-like material that’s easy to produce at low cost. It can stretch to 50 times its original length, and can heal itself from a scissor cut in the space of 24 hours at room temperature.

Just 5 minutes after being cut, the material can stretch to two times its original length again – not a bad power for a comic book superhero to have.

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The gene drive is quickly becoming one of the most controversial technologies of our time. Its possibilities are at once spectacular and alarming: by using genetic engineering to override natural selection during reproduction, a gene drive could allow scientists to alter the genetic makeup of an entire species. This could be used to eliminate diseases and protect natural habitats —but could also go horribly wrong in the wrong hands.

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