Talk:My Little Pony Equestria Girls: Friendship Games/@comment-3410511-20160321141931/@comment-10390252-20160321154853

The Ghostbusters' PKE meter wasn't just a random idea. Dan Akroyd did a lot of research into RL supernatural investigators. One of the things he found is that most paranormologists accept that supernatural activity creates electromagnetic anomalies - spikes in line voltage, unusual thermal spikes (usually downwards) and induced magnetic fields.

This is from small local-level effects that only affect a single building. However, the magic that the Sirens and the HuMane Six were throwing around were affecting large areas. Compared to your typical ghost, they're a nuclear bomb compared to a candle flame, powerful enough to be recorded as a large electromagnetic pulse by Twilight's lab equipment.

It is likely that Sci-Twi's sensor was picking up localised electromagnetic field anomalies. I'm not surprised that it was triggered by the portal. As the event horizon of a wormhole, the portal would have a 'skin' of 'orphan' virtual particles either originating from Equestria or whose counterpart had passed through the portal into Equestria. The portal is probably very lightly electrically charged, enough to give someone a distinct static shock if they touch the event horizon. It is probably slightly warmer than the surrounding environment by a few hudredths of a degree (enough for a scientific sensor to detect) due to the Hawking Radiation from the event horizon.