Indiana University basketball fans are awaiting Tuesday night's game against Georgetown (WTTG-TV-5, 7:30 p.m.) with great anticipation. They want to know how good these topranked Hoosiers really are.

Bob Hammel, the sports editor of the local newspaper says this town is mystified by Indiana's lofty ranking, what with an opening-game lineup that included two freshmen and a sophomore. Coach Bobby Knight says all polls at this time are "ludicrous."

"I've always felt that it's impossible for me to tell what kind of team we have until after a minimum of 10 games," Knight said today in his Assembly Hall office. "We enter into some games now that will really help us in analyzing and evaluating our team. And that's what December has always been for me."

Georgetown, unbeaten and, like Indiana basically untested in three games, will be the first of four straight nationally-ranked opponents Indiana faces in a 22-day period. Following Georgetown, the Hoosiers face Kentucky, Tolelo and North Carolina.

The talk of this town is freshman guard Isiah Thomas, whom Knight has described as the most talented player he has ever recruited. The 6-foot-1 player from Chicago has added quickness to Knight's famous over-playing, physical man-to-man defense.

Quickness was a missing ingredient of an Indiana team that returned all five starters from its National Invitation Tournament champions. Last year, the opposition made more steals than the Hoosiers and Indiana played a rather plodding offense.

This year, Thomas leads the team in steals and Indiana has almost a 3-1 ratio in its favor. As a result, the Hoosier have picked up their tempo somewhat in the first three games, averaging 72 shots per game, 20 more than last season.

It's a simple game," Knight said. "Most people . . . overcomplicate it."

And that is likely to be the most fascinating aspect of the Georgetown game. The Hoyas can play fast, medium or slowly. Coach John Thompson wants to see whether his team, which has at least as much talent as last season's 24-5 outfit, can keep its composure as it did last season under the departed team captain, Steve Martin.

Thompson wants a slow-paced game. He figures his team has a good chance to beat Indiana for the second straight year if the final score is in the 50s or 60s.

"The name of the game is tempo; don't let them press us out of our offense to the point we get ragged." Thompson said." We have to keep our concentration. The people without the ball have to move, because they deny so much. We can't stand around on the perimeter.

"It's a good test to see how we're running our offense. We're not going to play against anybody that's going to be any better at denying, because Bobby harps on that and harps on that. They play good team defense; it's a good challenge from our perspective."

To give some indication of Thomas' defensive value, one needs to look at his offensive stats (7.7 point average, 31.8 percent accuracy on field goals) and listen to Knight:

"Thomas is an extremely willing player. He works very hard. The 32 percent shooting is of no concern to me because of what he does other than that. If Thomas' only contribution was shooting, then I'd be concerned about that. But it isn't. He's played well to date."

Thomas and the man he will guard, Georgetown senior John Duren, are no strangers, after playing together on the United States team in the Pan American Games that won the gold medal under knight's coaching.

Also on that team were Indiana's Mike Woodson, who some pro scouts consider the No. 1 small senior forward in the country, and center Ray Tolbert. They are the other key players on this role-conscious team.

Woodson is the scorer, the zone buster and, according to Knight, a man who has worked hard to develop all phases of his game. Tolbert does the hard work to get Woodson those points, setting the inside picks, and playing excellent defense.

Indiana's inside game is somewhat weakened now because freshman Steve Bouchiep, a 6-8 "Mr. Indiana Basketball" selection last year, has a foot injury and has missed the past two games. "He will be an outstanding basketball player for us," Knight predicted, "and in some respects, he is our best inside player."

Glen Grunwald, a senior hobbled by injuries but efficient in Knight's style of basketball, has started in Bouchie's place.

The other starter is Randy Wittman, a 6-6 sophomore, who may be Indiana's best defensive player. He should be able to prove it this season since he will not have to defend smaller point guards, as he did last season.

That puts 6-9 sophmore Landon Turner and 6-5 Butch Carter, starters on the 22-12 NIT champs, on the bench.

"We've had a number of kids play reasonably well at times, and we perhaps have more players capable of playing now than in the last couple of years. But then, again, you find that out now," Knight said.

So it appears the chemistry is there for a run at the national championship Indiana last captured with its undefeated 1975-76 team. Knight is non-committal.

"I really don't know," he said. "That's the only answer I can give you. You ask related questions and I can't answer them because I've been with the team every day since Oct. 15 and I don't what kind of team it is. We haven't played against a full range of opponents to cover everything."

Tuesday's game will give each team some indication of how it measures up against a quality opponent. And Georgetown is certain to show Indiana a lot of zone defenses (1-3-1 and 2-3 matchup, each of which is aggressive and puts pressure on the ball).

Thompson will zone for at least two basic reasons. First, such a strategy should help keep the Hoyas out of foul trouble especially center Ed Spriggs and forward Craig Shelton in what figures to be a fierce game underneath the basket. Second, a zone usually forces a team to take longer to get an open shot, which makes for a slower pace.

Last season, Georgetown beat Indiana at Capital Centre. They will be facing a hostile crowd and the officials will be from the Midwest. But the Hoya strength last year was remarkable road success, winning at Penn, St. John's and Holy Cross. Indiana has lost 10 games in Assembly Hall since it opened in 1971.

"It's very important for us to stay in our offense," Duren said after practice today." Every college team is capable of beating the other at this level. You go out and play 100 percent and you can come out on top."