This is another what-if of the Pacific War.

We know that Japan simply couldn't win an attrition war against the Allies, however Japan was very, very close —more than once— to cause very severe setbacks to the Allies and even winning the war in 1942.

In April 1942 admiral Chuichi Nagumo took once again his mighty carrier fleet against the Allies, this time against the Indian Ocean bases at Ceylon.

First, Nagumo's planes destroyed British bases and docks at Colombo and swept the RAF there. Then they sank in less than ten minutes the heavy cruisers HMS Cornwall and HMS Dorsetshire. After that Nagumo sank the carrier HMS Hermes along destroyers HMS Vampire and HMS Tenedos. Incredibly, Nagumo turned back and went back to friendly waters.

The British force under admiral Sir James Somerville had then 2 carriers —HMS Indomitable and HMS Formidable—, 5 battleships, 5 light cruisers and 14 destroyers.

Admiral Nagumo had 5 heavy carriers, 4 battleships, 2 heavy cruisers, 1 light cruiser and 1 destroyer. He with his 350 planes had complete advantage upon the British. If he would have chosen to chase Somerville's force the entire British fleet in the Indian Ocean might have been annihilated. British destroyers, cruiser and battleships could have fought the Japanese ships, but they couldn't do absolutely nothing against Nagumo's overwhelming air superiority.

What would be the consequences?

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"War is less costly than servitude, the choice is always between Verdun and Dachau." - Jean Dutourd, French veteran of both world wars

"A mon fils: depuis que tes yeux sont fermes les miens n’ont cessé de pleurir." - Mère française, Verdun

If the British chose not to engage the Japanese they could simply have steamed West and / or South towards Africa or the Red Sea. In either case, the Japanese would have been hard pressed to follow without substancial tanker support they lacked.
The Japanese also lacked good scouting having neither submarines on picket or long range survellance aircraft available.
Now, had the Japanese brought a division or two and taken Celyon that would have made a difference. Then the British would have to come to them and engage the Japanese on their terms. Then the what-if would be could the British with their small and obsolesent airforce in India and two marginally capable carriers (after all between them they have about 90 aircraft and only about 15 Fulmar fighter aircraft)be able to counter such a move by the Japanese? If not, how would this have effected India.

Very good post, T. A. I was precisely thinking about fuel-supply and air reconnaisence.

Admiral Somerville obviously made the right move withdrawing to the African coasts. Therefore you're completely right about that Nagumo instead of chasing them would have had to make them come and attack him. Then, his planes would have finished the job and the Indian Ocean would have fell on Japanese hands too...

__________________
"War is less costly than servitude, the choice is always between Verdun and Dachau." - Jean Dutourd, French veteran of both world wars

"A mon fils: depuis que tes yeux sont fermes les miens n’ont cessé de pleurir." - Mère française, Verdun

After Ceylon, then Madagascar. The burning question is? why did they not take Ceylon?