The science and tech of Doctor Who

The ultimate solar power

The Doctor uses the energy of a star to power the TARDIS, but can humans truly tap into such solar energy potentials? If we wanted to harness the full energy of a star, we would need to create what is known as a Dyson sphere. In 1960, scientist Freeman Dyson first described the concept of a network of solar panels to completely envelop a star and tap into its immense energy output. The solar mega structure of a Dyson sphere, or shell, would theoretically comprise of millions of individual solar panel satellites capable of capturing, storing and transmitting the energy back to Earth for use. However, in order to construct such an array around a Sun-like star, we would require more material than currently exists in our entire Solar System!

Bottling a star 

If Earth’s engineering can’t reach the Sun to create a Dyson sphere, then why not recreate a star on Earth? The Sun’s nuclear fusion is made possible due to its immense mass and gravity heating its core to 15 million degrees Celsius. Within its internal incinerator, hydrogen atoms can fuse together to form helium. It’s this reaction that releases energy, and it’s a process that we could try to replicate.

Currently, we have mastered the process of splitting the atom to release energy, known as nuclear fission. However, if we could take inspiration from the Sun and succeed in engineering a viable fusion reactor to stick atoms together, our power-producing potential could be out of this world.

There are two main approaches to achieve nuclear fusion: magnetic or inertial confinement. Inertial confinement uses laser beams to focus energy and heat up hydrogen isotopes, forcing the atoms to come together to form helium. Magnetic confinement, however, uses magnetic fields to confine and compress hydrogen plasma at high temperatures until fusion occurs, generating helium and energy.

In both cases the energy released from fusion can be used to heat water, creating steam that in turn spins a turbine that can power a generator, ultimately producing electricity. With our current fusion reactor technology, however, the energy required to power the process of fusion is greater than the energy output of the reactors.

Don’t blink!

As one of the more creepy Doctor Who villains, the Weeping Angels can only be stopped when met with a human gaze – that is until you blink, of course. This sinister skill, however, isn’t just a sci-fi trick – it’s based on quantum physics.

Known as the quantum zeno effect, this is when a particle moving through space is halted when it is continually observed in what is essentially a particle game of What’s the time Mr Wolf? Several experiments, including one known as the ‘double-slit’ test, have found that particles act differently when observed, providing some of the first displays of the quantum zeno effect phenomenon.

Sonic science 

A screwdriver, pen, lipstick and gun – sonic technology has always been in the firm grip of the Doctor, her friends and enemies. At the press of a button, the Doctor can disarm a Silurian solider, sever a suspended rope and crack any lock… as long as it’s not made of wood.

The power of the sonic screwdriver is not merely the product of mechanical make-believe but follows the logic of high-kinetic sonic waves. The physical abilities of sonic technology can be demonstrated in acoustic levitation. Using a sound-emitting transducer, sound waves are sent upwards to an overhanging reflector, which reflects the waves back down. At a specific wavelength this sound pressure can hold an object in its grasp and appear to make it levitate. However, these sound waves can do much more than hold a ball in mid-air.

Sound waves, such as ultrasound, can be used to see inside the body, used at high frequencies to vibrate the dirt away when cleaning tanks, while infrasound can even be weaponised to affect hearing, balance and induce headaches.