Yes, but they suppousedly got 4000 times the maximal theoretical value. I'll repost one of my old comments with more details:
If you use a photon thruster (aka a laser or a flashlight in the right direction (or a microwave)), then the maximal thrust/energy ratio is at most 1/c = 3.33 nano-Newtons per Watt = 0.0033 uN/W = 0.0033 mN/KW.
Some of the experiments are few years old, but you can compare the current result with 0.0033 mN/KW. The results in the tables vary from 3x to 200000x the theoretical maximum of a photon thruster. I think that the typical current value is x4000.
It's a theoretical upper bound that is very easy to calculate using special relativity, and it depends on very fundamental laws, not tricky details of the universe.
The theoretical bound is so fundamental, that it's even true if you use a graviton thruster instead of a photon thruster. This example is not totally made up, someone have an alternative impossible massless drive that "push against the far away stars". They claimed also a thrust/energy ratio > 0.0033 mN/KW, so it was also impossible from a theoretical point of view.
Also, for the EmDrive, someone proposed that it emits twin photons that somehow cancel each other, but the pair still carry momentum. That explanation extremely wrong.
If you use a photon thruster (aka a laser or a flashlight in the right direction (or a microwave)), then the maximal thrust/energy ratio is at most 1/c = 3.33 nano-Newtons per Watt = 0.0033 uN/W = 0.0033 mN/KW.
Someone compiled here two lists of experiments: http://forum.nasaspaceflight.com/index.php?topic=36313.msg13... http://emdrive.wiki/Experimental_Results
Some of the experiments are few years old, but you can compare the current result with 0.0033 mN/KW. The results in the tables vary from 3x to 200000x the theoretical maximum of a photon thruster. I think that the typical current value is x4000.
It's a theoretical upper bound that is very easy to calculate using special relativity, and it depends on very fundamental laws, not tricky details of the universe.
The theoretical bound is so fundamental, that it's even true if you use a graviton thruster instead of a photon thruster. This example is not totally made up, someone have an alternative impossible massless drive that "push against the far away stars". They claimed also a thrust/energy ratio > 0.0033 mN/KW, so it was also impossible from a theoretical point of view.
Also, for the EmDrive, someone proposed that it emits twin photons that somehow cancel each other, but the pair still carry momentum. That explanation extremely wrong.