Cryptic Crossword #28,858

1, 15

Albert and his work (theoretical, not real) dealt with the theory of relativity? (5,2,7,4,5)

8

I will stop working in an American university (5)

9

How food can be served without spending anything from the monthly allowance (2.6)

11

It's nice to be back on the road with a better car (7)

12

Cad turned against the queen and the popular old king (7)

13

Wake up around noon to wash (5)

15

See 1

17

Nature being uncovered, questionable mask - it's explained here with illustrations (4.5)

20

The round container contains a tablet and a lot of water (5)

21

Sports Article Getting Old Louis Wrong? (7)

23

The return home is largely painful for the composer (7)

25

It may be true: listen, it was the language of the 12 (8)

26

The love story of a magazine captivates his daughter (5)

27

Early work might involve meeting a colleague at a steak bar, perhaps (5.9)