How Old Is Our World, Really?

"How can Judaism claim that the world is only 5,800 years old? There is scientific proof that the world was created billions of years ago. How is that possible?!" This is one of the most common questions. The gaping gap between what science asserts and what Judaism asserts about the age of the world creates the impression that Judaism "turned out to be wrong," and from there comes the firm conclusion that Judaism should not be given too much weight in our lives. So let us hear, once and for all, what Judaism has to say about this.

The scientific theory accepted today holds that the Universe was created 13.8 billion years ago, while the Torah explains that it happened 5,783 years ago (as of the year 5783 on the Jewish calendar, 2023). In fact, it was only about sixty years ago that scientists came to the conclusion that the world was created at a specific moment in time, rather than having always existed, as was previously believed. For most of history the prevailing scientific opinion was that the world had existed forever. Aristotle, the Greek philosopher whose influence was immense throughout the Middle Ages, wrote that something immaterial cannot become material reality out of nothing, and so the conclusion suggested itself that the Universe is eternal and has always existed. This was the scientific consensus right up to the beginning of the twentieth century. Many scientists ridiculed the idea that the world had been created at some point; it seemed utterly implausible.

Only in the 1960s did scientists accept the Big Bang theory, according to which the world was created by the explosion of an enormous concentration of energy called a "singularity." In many respects the principles of this theory are strikingly similar to the description of Creation in the book of Genesis (you can read about this in detail in the book "In the Beginning" by Professor Nathan Aviezer, which lays out the parallel between the Torah's account and that of science).

According to the Big Bang theory, the explosion produced a powerful shock wave and tremendous heat, from which the first matter was formed. From the moment of Creation the Universe began to expand, and it has been expanding ever since. At the moment of the initial explosion, cosmic background radiation was scattered through space, and it has been present everywhere in the Universe ever since. This radiation is the only remnant that survives from that explosion. The farther it "moves away" from the original point of the explosion, the lower its temperature. Measuring the temperature of the cosmic background radiation in space is today the principal method of estimating how much time has passed since that initial explosion. Additional, less precise methods include radioactive dating and calculations based on the speed at which galaxies are receding from the Milky Way and the distances to those galaxies.

Today the approach generally accepted in the scientific community is that the world was created about 14 billion years ago. The Torah, by contrast, explains that the world was created only 5,781 years ago.

The main problem with the scientific calculation of the world's age lies in its underlying assumption. To calculate the rate of cosmic radiation (or the temperature, or any other parameter), one must assume that the laws of nature have not changed since the "Big Bang." This principle, called the "principle of uniformity (uniformitarianism)," states that the laws of nature today are identical to the laws of nature that have always existed (for instance, the force of gravity, the behavior of matter at a given temperature, the speed of light, atmospheric pressure and so on). Without this underlying assumption, any scientific study or measurement concerning what happened at the Creation of the world is meaningless. If the parameter being measured has changed since then, we cannot rely on it to learn the age of the Universe.

Consequently, if the pace of processes and of time at the beginning of Creation differed greatly from today's pace, there is no difficulty at all in reconciling the Torah's explanation of the world's age. Creation at its beginning proceeded at an entirely different pace — a far faster one, by analogy with the pace at which an infant develops at the start of its life. Today's pace of the world is much slower, like that of an adult. Accelerated processes took place in the first moments of Creation, so the pace of events was far faster than it is today, as Professor Nathan Aviezer explains:

"According to the generally accepted Big Bang theory, a long series of dramatic cosmological transformations took place within a very short span of time, at the very beginning of the Universe. This point was particularly emphasized by Professor Steven Weinberg, who chose to title his book on modern cosmology 'The First Three Minutes.' Professor Weinberg needed 151 pages to describe the fateful cosmological changes that occurred in just three minutes!" ("In the Beginning," Professor Nathan Aviezer, p. 26).

Jewish tradition speaks of entirely different conditions that prevailed in different periods of Creation. Thus, for example, the portion of Noach describes how the world was inundated by the Flood. After the Flood, which lasted 40 days without pause, a Divine promise was given that such an event would not recur: "While the earth remains, seedtime and harvest, and cold and heat, and summer and winter, and day and night shall not cease" (Bereishit 8:22). From this verse one can understand that the Flood was not simply a very heavy rain, but that the order of nature, including the order of time, changed completely at that time — the length of the day, the seasons and even the temperature were altered (see Rashi's commentary on this verse). Science has no way to calculate the changes that took place then, all the more so since almost no trace of these events remains today, apart from the mention in the book of the Torah.

The pace at which the human body develops changes dramatically between the start of life and a later stage. During the first year of life a child grows by roughly 25 cm. By contrast, an adult of 50 is hardly likely to gain 25 cm in height in a year. In other words, the pace of the human body's development changes dramatically from the beginning of life compared with a later stage.

What do scientists do when they test the age of the world? They measure the rate at which data on Earth are changing in their present state and assume that the rate of change has always been constant. Given this underlying assumption, it is no surprise that the age of the Universe they claim is so vast.

To illustrate, take an example: a 17-year-old boy has grown 1 cm in the past year. If we apply the scientific assumption that the growth rate is constant (1 cm per year) to an infant, we arrive at an absurd conclusion. Suppose an infant is born 50 cm long, and at the age of two is 87 cm tall (a gain of 37 cm). According to the scientific approach to calculating age, which assumes a constant growth rate (1 cm per year), this infant, having gained 37 cm, is at least 37 years old!

Judaism maintains that the pace of processes and of time at the beginning of Creation differed greatly from today's pace. One day today is not equal to one day at the start of Creation. Creation proceeded at an entirely different, far faster pace, like an infant at the beginning of its life. Today's pace is much slower, like that of an adult. This is why science claims that the world is far older than Judaism says. From this it is clear that relying on the principle of uniformity to determine the age of the world is problematic.

An additional explanation that reconciles the question of the world's age according to Judaism is this: science assumes that Creation developed from a zero point, whereas the Torah reveals to us that the world was created by God in a mature state, one that looks developed and complete. The Oral Torah says: "All the works of Creation were created in their full stature" (Tractate Chullin 60a). That is, the first man was not created as a nursing, helpless infant but as a grown man of 20. The other animals and plants, too, were created in their adult form. This fact also explains why science claims the Universe is far older than it really is.

If we return to the example of the infant, it was not born with zero height but with an initial height of 50 cm. In exactly the same way, Judaism maintains that Creation was not made from zero but in a mature state. Science, on the contrary, holds that Creation began from zero. Therefore, when calculating the age of the world, it proceeds from the premise that at the world's creation there was nothing.

If we calculate the infant's age on the basis of science's underlying assumptions (the initial state is zero, and the rate of change is identical to the present rate), we will conclude that a two-year-old infant who is 87 cm tall is at least 87 years old!

In conclusion, none of us was present at the world's first moments, nor in the years that followed. In light of this, there is no need whatsoever to assume that the conditions prevailing in Creation today are the same as those that prevailed in the past. Consequently, researchers, however wise and great they may be, cannot establish the age of the world as an accomplished fact — unless they rely exclusively on theoretical underlying assumptions.