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Quantum computers, quantum cryptography and quantum (insert name here) are often in the news these days. Articles about them inevitably refer to entanglement, a property of quantum physics that makes all these magical devices possible.

Einstein called entanglement “spooky action at a distance,” a name that has stuck and become increasingly popular. Beyond just building better quantum computers, understanding and harnessing entanglement is also useful in other ways.

For example, it can be used to make more accurate measurements of gravitational waves, and to better understand the properties of exotic materials. It also subtly shows up in other places: I have been studying how atoms bumping into each other become entangled, to understand how this affects the accuracy of atomic clocks.

During one of these phase transitions (which happened when the universe was less than a second old), the axions of string theory didn’t appear as particles. Instead, they looked like loops and lines — a network of lightweight, nearly invisible strings crisscrossing the cosmos.

This hypothetical axiverse, filled with a variety of lightweight axion strings, is predicted by no other theory of physics but string theory. So, if we determine that we live in an axiverse, it would be a major boon for string theory.

How can we search for these axion strings? Models predict that axion strings have very low mass, so light won’t bump into an axion and bend, or axions likely wouldn’t mingle with other particles. There could be millions of axion strings floating through the Milky Way right now, and we wouldn’t see them.

Happy New year everyone! We wanted to give you an inside look as to what happens on our Dr. Joe live calls that take place once a month. Here’s a moment from our last Dr. Joe live call.

⁣ Some of the subjects Dr. Joe may address: latest scientific discoveries; health and wealth; love and relationships; neuroscience and epigenetics; happiness and vitality; the quantum model of reality; how you can make great and lasting changes in yourself and your life!⁣

⁣ With his vast experience and deepening knowledge of how each one of us can unlock unlimited abilities and transform our lives for the better, these classes offer you a unique opportunity to continually learn and interact with Dr. Joe! If you want to take it a step further in the work, Dr. Joe live is a great way to deepen your understanding, keep you plugged into the community and interact with Dr. Joe personally.⁣.

As 2019 winds to a close, the journey towards fully realised quantum computing continues: physicists have been able to demonstrate quantum teleportation between two computer chips for the first time.

Put simply, this breakthrough means that information was passed between the chips not by physical electronic connections, but through quantum entanglement – by linking two particles across a gap using the principles of quantum physics.

We don’t yet understand everything about quantum entanglement (it’s the same phenomenon Albert Einstein famously called “spooky action”), but being able to use it to send information between computer chips is significant, even if so far we’re confined to a tightly controlled lab environment.

Integrated optics provides a versatile platform for quantum information processing and transceiving with photons1,2,3,4,5,6,7,8. The implementation of quantum protocols requires the capability to generate multiple high-quality single photons and process photons with multiple high-fidelity operators9,10,11. However, previous experimental demonstrations were faced by major challenges in realizing sufficiently high-quality multi-photon sources and multi-qubit operators in a single integrated system4,5,6,7,8, and fully chip-based implementations of multi-qubit quantum tasks remain a significant challenge1,2,3. Here, we report the demonstration of chip-to-chip quantum teleportation and genuine multipartite entanglement, the core functionalities in quantum technologies, on silicon-photonic circuitry. Four single photons with high purity and indistinguishablity are produced in an array of microresonator sources, without requiring any spectral filtering. Up to four qubits are processed in a reprogrammable linear-optic quantum circuit that facilitates Bell projection and fusion operation. The generation, processing, transceiving and measurement of multi-photon multi-qubit states are all achieved in micrometre-scale silicon chips, fabricated by the complementary metal–oxide–semiconductor process. Our work lays the groundwork for large-scale integrated photonic quantum technologies for communications and computations.