Are Reagan and Chernenko ready to do business?

The main action in world affairs this week continues to be largely out of public sight in the back rooms of Moscow and Washington. There is as yet no clear answer to the main question of whether both sides are ready to do serious business.

Each, of course, is groping for some hint as to how ready the other is. We can assume that when Moscow's head man, Konstantin Chernenko, received visiting American tycoon Armand Hammer at the Kremlin his real question was: ''Does Reagan want to deal?''

In Washington, there were two indicators of the struggle going on behind the scenes over what, if anything, United States Secretary of State George Shultz will be able to offer when he meets his Soviet opposite number, Andrei Gromyko, in Geneva next month.

One indication was that President Reagan named Paul Nitze, who has been the chief US negotiator in strategic arms limitation talks with the Soviets, to be Mr. Shultz's adviser for the Jan. 7-8 talks. Mr. Nitze has moved into an office on the seventh floor corridor at the State Department where Mr. Shultz and his top deputies work.

Another indication of the struggle in Washington was postponement of a long-promised report to Congress on alleged Soviet violations of SALT I and II treaties. These alleged violations have been the main weapon of those elements in the administration that oppose any new agreements on weapons. The argument advanced by Richard Perle, assistant secretary of defense for international security policy, and champion of the anti-agreement forces at the Pentagon, is that the Soviets violate agreements when it suits them, therefore the US should never agree to anything that is not verifiable and enforceable.

Demand by some senators for the report, the deferring of its release, and many a ''leak'' over its alleged contents are all surface signs of the great ''war of the two Richards'' (Richard Perle at Defense vs. Richard Burt, assistant secretary of state for European affairs) that has preceded Mr. Reagan's decision to open a new dialogue with the Soviets in the first month of his second term.

As far as outside observers and reporters can tell, Mr. Perle lost a round when the President decided to offer the Soviets ''umbrella'' talks. Under these, the Russians could forget that they walked out of all the arms control talks last spring with a declaration that they would never return until the US removed its new Pershing II and cruise missiles from Europe.

The missiles have not been removed and will not be. Deployment continues. But the Soviets are going to resume talking because the ''umbrella'' will permit broad-ranging talks over almost any subject either side wishes to bring up.

Perle has not given up the fight he has been waging since his old days as chief foreign-policy adviser to Sen. Henry (''Scoop'') Jackson on Capitol Hill before he moved to the Pentagon as chief foreign-policy adviser to Secretary of Defense Caspar Weinberger.

When on the Jackson staff on the Hill, Perle obtained top-secret material from the Central Intelligence Agency from personal informants. It included some of the same material in the current maneuvering over alleged Soviet

violations. Perle is indefatigable.

The week also brought interim developments in both Central America and the Middle East.

In El Salvador, there was a second round of ''peace'' talks between government and rebel delegations. The rebels made exorbitant demands which the government rejected. The exchange proved that the military situation is still too fluid and unsettled for either side to be ready for a compromise settlement. Rebels claimed a successful ambush of government forces. This tended to undermine an assumption of late that the government forces are gaining the military decision. As long as the military situation is fluid, it is unlikely that the rebels will be ready to make a potentially acceptable offer.

In the Mideast, King Hussein of Jordan went to Cairo in an elaborately staged renewal of formal good relations between Jordan and Egypt. This happened just after the US had resumed diplomatic relations with Iraq and just before Richard W. Murphy, the State Department's assistant secretary for Near Eastern affairs, headed back to the area for another round of explorations.

Mr. Murphy is described among his colleagues as being ''a good listener.'' He likes to sit down with an Arab or Israeli diplomat and hear what they have to say. Sometimes he can carry a useful message from one to another. During the coming week or so he will be able to do just that between Tel Aviv and Damascus since Israelis and Syrians may want to exchange thoughts via Murphy even though they would not talk directly to each other.

Probably the general situation in the Middle East is no more ready for the diplomats than it is in El Salvador, but there have been changes of late that can make a difference in the future. The renewal of formal and friendly relations between Jordan and Egypt and the movement of Iraq back into association with the US could lead to collaboration among those three neighbors of Israel under US mediation.

King Hussein of Jordan has joined President Hosni Mubarak of Egypt in asserting their readiness to negotiate over peace with Israel on a basis of United Nations Resolution 242, which contemplates Arab acceptance of the existence of Israel in return for Israeli withdrawal from occupied territories.

King Hussein played host the week before to a convention of the Palestine Liberation Organization that saw the revival of Yasser Arafat as leader of that organization. Mr. Arafat is supported by the moderate wing of the PLO which is willing to talk and think in terms of Resolution 242, which means willingness to consider accepting the existence of Israel. The more radical wing holds out for the ultimate goal of the liquidation of Israel.

No one involved in all of this diplomacy thinks that a fresh push toward Arab-Israel peace is in sight, but most agree that the general situation is a bit more fluid and hence interesting.