#deflector shields

[chernobog13]

The Enterprise under attack from Klingons in the Star Trek: The Animated Series episode The Time Trap.

[swan2swan]

Has Star Wars fandom ever discussed why the Death Star didn’t have shields like the ones on Scarif, Hoth, and Endor?

Obviously the basic explanation is “that kind of power creep hadn’t happened yet.” Shield generators in general weren’t really established in the first movie (the Falcon kept exploding when it got shot, X-wings got ripped apart just as easily as TIEs, they might not even have had hyperdrives, but that’s another story), and the best extent was the “ray shielded” exhaust port and the force field on the docking bay that allowed hangar crews to enter a docking bay that a spaceship had just entered (again: another abandoned concept in later films, though I believe it was first a thing in the ESB special edition, when Vader returns to his destroyer). 

But no one likes the old “they hadn’t thought of it yet” explanation. Obviously power requirements for that kind of shield are incredible, so you can’t just slap that caliber of protection onto an ISD--it’s possible, even, that Hoth had multiple projectors that were overlapping and relieving one another, so as soon as you break Shield A, Shield C turns on, and you’re still hitting Shield B, and by the time B breaks, A is back online, meaning that you have an endless cycle going until Veers cuts the power. Even if you had the power capacity, you would still need a suitable arrangement of shield generators.

My hypothesis would be that planetary shields probably just add charge to an area of a planet’s own ionosphere. The Death Star is big, but it’s still not big enough to generate that kind of energy--especially without its own atmosphere. Though I don’t know if the shield generator in Rogue One is at the right height...

Anyway. This is my “science of Star Wars” cud-chewing post for the day. Time to go to work.

[catfoxwolf]

Take evasive action. (Full view here.)

[no-rhythm]

Warping space has other advantages as well. Clearly, if spacetime becomes strongly curved in front of the Enterprise, then any light ray, or phaser beam, for that matter, will be deflected away from the ship. This is doubtless the principle behind deflector shields. Indeed, we are told that the deflector shields operate by "coherent graviton emission." Since gravitons are by definition particles that transmit the force of gravity, then "coherent graviton emission" is nothing other than the creation of a coherent gravitational field. A coherent gravitational field is, in modern parlance, precisely what curves space!

Lawrence Krauss, The Physics of Star Trek