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The Surprising Story of the First Microprocessors

You thought it started with the Intel 4004, but the tale is more complicated

12 min read
Photo: INTEL
Photo: INTEL

Transistors, the electronic amplifiers and switches found at the heart of everything from pocket radios to warehouse-size supercomputers, were invented in 1947. Early devices were of a type called bipolar transistors, which are still in use. By the 1960s, engineers had figured out how to combine multiple bipolar transistors into single integrated circuits. But because of the complex structure of these transistors, an integrated circuit could contain only a small number of them. So although a minicomputer built from bipolar integrated circuits was much smaller than earlier computers, it still required multiple boards with hundreds of chips.

In 1960, a new type of transistor was demonstrated: the metal-oxide-semiconductor (MOS) transistor. At first this technology wasn’t all that promising. These transistors were slower, less reliable, and more expensive than their bipolar counterparts. But by 1964, integrated circuits based on MOS transistors boasted higher densities and lower manufacturing costs than those of the bipolar competition. Integrated circuits continued to increase in complexity, as described by Moore’s Law, but now MOS technology took the lead.

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Quantum Computing for Dummies

New guide helps beginners run quantum algorithms on IBM's quantum computers over the cloud

3 min read
An image of the inside of an IBM quantum computer.
IBM

Quantum computers may one day rapidly find solutions to problems no regular computer might ever hope to solve, but there are vanishingly few quantum programmers when compared with the number of conventional programmers in the world. Now a new beginner's guide aims to walk would-be quantum programmers through the implementation of quantum algorithms over the cloud on IBM's publicly available quantum computers.

Whereas classical computers switch transistors either on or off to symbolize data as ones or zeroes, quantum computers use quantum bits, or "qubits," which because of the peculiar nature of quantum physics can exist in a state called superposition where they are both 1 and 0 at the same time. This essentially lets each qubit perform two calculations at once. The more qubits are quantum-mechanically linked, or entangled (see our explainer), within a quantum computer, the greater its computational power can grow, in an exponential fashion.

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This Wearable Neck Patch Can Diagnose Concussions

Self-powered sensors convert neck strain into electrical pulses to detect head trauma in athletes

4 min read
image of back of man's head and shoulders with a patch taped to his lower neck; right image is a time lapse image of a man's head extending far forward and back, simulating a case of whiplash

The prototype patch in this research is shown in (a) on the left; on the right (b) is the kind of head rotation that can yield an electrical response from the patch.

Juan Pastrana

Nelson Sepúlveda was sitting in the stands at Spartan Stadium, watching his hometown Michigan State players bash heads with their cross-state football rivals from the University of Michigan, when he had a scientific epiphany.

Perhaps the nanotechnologies he had been working on for years—paper-thin devices known as ferroelectret nanogenerators that convert mechanical energy into electrical energy—could help save these athletes from the ravages of traumatic brain injury.

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